Allied invasion of Italy

The Allied invasion of Italy was the Allied landing on mainland Italy on September 3, 1943, by General Harold Alexander's 15th Army Group (comprising Lieutenant General Mark Clark's U.S. Fifth Army and General Bernard Montgomery's British Eighth Army) during the Second World War. The operation followed the successful invasion of Sicily during the Italian Campaign. The main invasion force landed around Salerno on the western coast in Operation Avalanche, while two supporting operations took place in Calabria (Operation Baytown) and Taranto (Operation Slapstick). {| class="toc" id="toc"

Contents
[hide] *1 Background
 * 1.1 Allied strategy
 * 1.2 Plan
 * 1.3 Axis defensive organization
 * 2 Battle
 * 2.1 Operations in southern Italy
 * 2.2 Salerno landings
 * 2.3 Consolidation of the beachhead
 * 2.4 German counterattacks
 * 2.5 Eighth Army ordered to apply pressure
 * 2.6 German withdrawal
 * 2.7 Salerno mutiny
 * 2.8 Further Allied advances
 * 3 Aftermath
 * 3.1 Clark's award
 * 4 See also
 * 5 Footnotes
 * 6 References
 * 7 Further reading
 * 8 External links
 * }

Allied strategy
Following the defeat of the Axis Powers in North Africa, there was disagreement between the Allies as to what the next step should be. Winston Churchill in particular wanted to invade Italy, which in November 1942 he called "the soft underbelly of the axis" (and General Mark Clark later called "one tough gut").[1] Popular support in Italy for the war was declining, and he believed an invasion would remove Italy, and thus the influence of axis forces in the Mediterranean Sea, opening it to Allied traffic. This would very materially reduce the amount of scarce shipping capacity needed to supply Allied forces in the Middle East and Far East[2] at a time when the disposal of Allied shipping capacity was in crisis[3] and increase British and American supplies to the Soviet Union. In addition, it would tie down German forces, keeping them away from the Russian front. Stalin had been pressing to open a "second front" in Europe, which would weaken the Wehrmacht's invasion of Russia.

However, General George Marshall and much of the American staff wanted to avoid operations that might delay an invasion of Europe, discussed and planned as early as 1942, which finally materialized as Operation Overlord. When it became clear that no invasion could be undertaken in 1943, it was agreed to invade Sicily, with no commitment made to any follow-up operations. However, both Roosevelt and Churchill accepted the necessity of Allied armies continuing to engage the Axis in the period after a successful campaign in Sicily and before the start of one in northwest Europe [4] The discussion continued through the Trident Conference in Washington in May but it was not until late July, after the course of the Sicily campaign had become clear and with the fall of Mussolini, that the Joint Chiefs of Staff instructed Eisenhower to go ahead at the earliest possible date.[5]

Joint Allied Forces Headquarters AFHQ were operationally responsible for all Allied land forces in the Mediterranean theatre, and it was they who planned and commanded the invasion of Sicily and the Italian mainland.

The Allied invasion of Sicily in July 1943, codenamed Operation Husky, was highly successful, although many of the Axis forces managed to avoid capture and escape to the mainland. To the Axis, this was viewed as a success. More importantly in late July a coup deposed Benito Mussolini as head of the Italian government, which then began approaching the Allies to make peace. It was believed a quick invasion of Italy might hasten an Italian surrender and produce quick military victories over the German troops that could be trapped fighting in a hostile country. However, Italian (and more so German) resistance proved relatively strong, and fighting in Italy continued even after the fall of Berlin. In addition, the invasion left the Allies in a position of supplying food and supplies to conquered territory, a burden which would otherwise have fallen on Germany. As well, Italy occupied by a hostile German army would have created additional problems for the German Commander-in-Chief Albert Kesselring.[6]

Plan
Map of the Invasion of Italy.Salerno D-Day planFurther information: Allied Invasion of Italy Order of BattlePrior to Sicily, Allied plans envisioned crossing the Strait of Messina, a limited invasion in the "instep" area (Taranto), and advancing up the toe of Italy, anticipating a defense by both German and Italian forces. The overthrow of Benito Mussolini and the Fascisti made a more ambitious plan feasible, and the Allies decided to supplement the crossing of the Eighth Army with a seizure of the port of Naples. They had a choice of two landing areas: one at the Volturno River basin and the other at Salerno, both at the range limits of Allied fighter planes based in Sicily. Salerno was chosen because it was closer to air bases, experienced better surf conditions for landing, allowed transport ships to anchor closer to the beaches, had narrower beaches for the rapid construction of exit roads, and had an excellent pre-existing road network behind the beaches.

Operation Baytown was the preliminary step in the plan in which Eighth Army, under General Bernard Montgomery would depart from the port of Messina on Sicily, to cross the Straits of Messina and land near the tip of Calabria (the "toe" of Italy), on 3 September 1943. The short distance from Sicily meant landing craft could launch from there directly, rather than be carried by ship. V British Corps' 5th Infantry Division would land on the north side of the "toe" while its 1st Canadian Infantry Division would land at Cape Spartivento on the south side. General Montgomery was strongly opposed to Operation Baytown. He predicted it would be a waste of effort since it assumed the Germans would give battle in Calabria; if they failed to do so, the diversion would not work, and the only effect of the operation would be to place the Eighth Army 300 mi (480 km) south of the main landing at Salerno. He was proved correct; after Operation Baytown the Eighth Army marched 300 miles north to the Salerno area against no opposition other than engineer obstacles.

Plans for the use of airborne forces took several forms, all of which were cancelled. The initial plan to land glider-borne troops in the mountain passes of the Sorrento Peninsula above Salerno was abandoned 12 August. Six days later it was replaced by Operation Giant, in which two regiments of the 82nd U.S. Airborne Division would seize and hold crossings over the Volturno River. This was at first expanded to include the entire division, including an amphibious landing by the glider regiment, then deemed logistically unsupportable and reduced to a two-battalion drop at Capua to block the highway there. The Italian surrender on 3 September cancelled Operation Giant I and replaced it with Operation Giant II, a drop of the 504th Parachute Infantry Regiment on Stazione di Furbara and Cerveteri airfields, 25 mi (40 km) northwest of Rome, to aid Italian forces in saving Rome from the Germans, a condition of the Italian armistice. Because the distance from the Allied beachheads precluded any substantial Allied support of the airborne troops, Brig. Gen. Maxwell D. Taylor, 82nd Airborne's Assistant Division Commander, was spirited into Rome to assess the willingness of Italian troops to cooperate with the Americans. Taylor's judgment was the operation would be a trap and he advised cancellation, which occurred late on the afternoon of 8 September as troop carriers were preparing to take off.

The main landings (Operation Avalanche) were scheduled to take on 9 September, during which the main force would land around Salerno on the western coast. It would consist of the U.S. Fifth Army under Lieutenant General Mark W. Clark, comprising the U.S. VI Corps under Major General Ernest J. Dawley, the British X Corps under Lieutenant General Richard McCreery, with 82nd Airborne in reserve, a total of eight divisions and two brigade-sized units. Its primary objectives were to seize the port of Naples to ensure resupply, and to cut across to the east coast, trapping Axis troops further south. The naval task force of warships, merchant ships and landing craft totaling 627 vessels came under the command of Vice Admiral Kent Hewitt.[7] Part of Hewitt's command was Force V which included five aircraft carriers to provide air cover for the landings. Cover for the task force was provided by Force H, a group of four British battleships and two fleet carriers with destroyers in support, which was directly subordinate to the C–in–C Mediterranean Admiral of the Fleet Sir Andrew Cunningham.[7]

In the original planning, the great attraction of capturing the important port of Taranto in the "heel" of Italy had been evident and an assault had been considered but rejected because of the very strong defenses there. However, with the signing of the armistice with the Italians on 3 September the picture changed. It was decided to carry the British 1st Airborne Division to Taranto using British warships, seize the port and several nearby airfields and follow up by shipping in British V Corps and a number of fighter squadrons. The airborne division, which was undergoing training exercises in two locations 400 mi (640 km) apart, was ordered on 4 September to embark on 8 September. With such short notice to create plans, Operation Slapstick was soon nicknamed Operation Bedlam.[8]

The Avalanche plan was daring but flawed; Fifth Army would be landing on a very broad 35 mi (56 km) front, using only three assault divisions (two British in X Corps, one American in VI Corps),[9] and the two Corps were widely-separated both in distance (12 mi (19 km) and by the Sele River.[10] Clark initially provided no troops to cover the river, offering the Germans an easy route to attack, and only belatedly landed two battalions to protect it.[10] Furthermore, the terrain was highly favorable to the defender. Planning for the Salerno phase was accomplished in only forty-five days, rather than the months that might be expected.[10] A U.S. Army Ranger force under Colonel William O. Darby consisting of three U.S. Ranger battalions and two British Commando units was tasked with holding the mountain passes leading to Naples, but no plan existed for linking the Ranger force up with X Corps' follow-up units. Finally, although tactical surprise was unlikely, Clark ordered no naval preparatory bombardment or naval gunfire support take place, despite experience in the Pacific Theatre demonstrating it was necessary.[11] [page needed] (Major General Fred Walker, commanding 36th "Arrowhead" Division, believed the defenders, from LXXVI Panzer Corps,[citation needed] were too scattered for it to be effective.)<sup class="reference" id="cite_ref-Terdoslavich.2C_p.157_9-3">[10]

On the German side, Albrecht von Kesselring lacked the strength to push the Salerno landing back, and was refused two panzer divisions from northern Italy to assist him.<sup class="reference" id="cite_ref-Terdoslavich.2C_p.157_9-4">[10]

Operation Avalanche was planned under the name Top Hat and supported by a deception plan, Operation Boardman, a false threat of an Allied invasion of the Balkans.

Axis defensive organization
In mid-August, the Germans had activated Army Group B (Heeresgruppe B) under Erwin Rommel with responsibility for German troops in Italy as far south as Pisa.<sup class="reference" id="cite_ref-11">[12] Army Command South (OB Süd) under Albert Kesselring continued to be responsible for southern Italy<sup class="reference" id="cite_ref-12">[13] and the German High Command formed a new army headquarters to be Army Command South's main field formation. The new Tenth Army (10. Armee) headquarters, commanded by Heinrich von Vietinghoff, was activated on 22 August.<sup class="reference" id="cite_ref-13">[14] German Tenth Army had two subordinate corps with a total of six divisions which were positioned to cover possible landing sites. Under XIV Panzer Corps (XIV Panzerkorps) was Hermann Göring Panzer Division (Fallschirm-Panzer Division 1 Hermann Göring), 15th Panzergrenadier Division (15. Panzergrenadier-Division) and 16th Panzer Division (16. Panzer-Division); and under LXXVI Panzer Corps (LXXVI Panzerkorps) was 26th Panzer Division (26. Panzer-Division), 29th Panzergrenadier Division (29. Panzergrenadier-Division) and 1st Parachute Division (''1. Fallschirmjäger-Division'').<sup class="reference" id="cite_ref-14">[15] von Vietinghoff specifically positioned the 16th Panzer Division in the hills above the Salerno plain.

Operations in southern Italy
US General Mark Wayne Clark on board USS Ancon during the landings at Salerno, Italy, 12 September 1943.Map of the Salerno Beachhead at the end of 11 September 1943On 3 September 1943, British Eighth Army's XIII Corps, which was composed of British and Canadian formations, launched Operation Baytown under General Bernard Montgomery's direction. Opposition to the landings was light and the Italian units surrendered almost immediately. Albert Kesselring and his staff did not believe Calabria landings would be the main Allied point of attack, the Salerno region or possibly even north of Rome being more logical. He had already therefore ordered General Traugott Herr's LXXVI Panzer Corps to pull back from engagement with 8th Army leaving only 29th Panzer Grenadier Division's 15th Panzergrenadier Regiment in the 'toe' of Italy. By 3 September, most of this unit was in prepared positions at Bagnara, some 25 mi (40 km) from the landings which it had orders to hold until 6 September. After this they were to withdraw to join the rest of 29th Panzergrenadier Division which was concentrating at Castrovillari, some 80 mi (130 km) to the rear. The Krüger Battle Group (two battalions of 71st Panzergrenadier Regiment, 129th Reconnaissance Battalion and detachments of artillery and engineers) under 26th Panzer Division, would then stand at Nicotera, roughly 15 mi (24 km) up the coast from Bagnara.<sup class="reference" id="cite_ref-Molony239_15-0">[16]

On 4 September, 5 Division reached Bagnara, linked up with 1st Special Reconnaissance Squadron (which arrived by sea) and drove 3/15th Panzergrenadier Regiment from its position. On 7 September, contact was made with the Krüger Battle Group. On 8 September, 231st Brigade was landed by sea at Pizo, some 15 miles (24 km) behind the Nicotera defenses. They found themselves attacked from the north by a mobile force from 26th Panzer Division and from the south by the Krüger Battle Group which was withdrawing from the Nicotera position. After an initial attack which made no headway, the Krüger Battle Group veered away but the northern attack continued throughout the day before the whole German force withdrew at dusk.<sup class="reference" id="cite_ref-16">[17]

Progress was slow as demolished bridges, roadblocks and mines delayed Eighth Army. The nature of the countryside in the toe of Italy made it impossible to by-pass obstacles and so the Allies' speed of advance was entirely dependent on the rate at which their engineers could clear obstructions.<sup class="reference" id="cite_ref-Molony239_15-1">[16] Thus, Montgomery's objections to the operation were proved correct: the Eighth Army could not tie down German units that refused battle and the main obstacle to their advance was the terrain and German demolitions of roads and bridges.

By 8 September, Kesselring had concentrated Heinrich von Vietinghoff's 10th Army, ready to make a rapid response to any Allied landing.<sup class="reference" id="cite_ref-17">[18] In Calabria, Herr's LXXVI Panzer Corps had two divisions concentrated in the Castrovillari area. Its third division, 1st Parachute Division (1. Fallschirmjäger-Division), was deployed toward Taranto. The rearguard in the toe was BattleGroup von Usedom, comprising a single battalion (1/67th Panzergrenadier Regiment) with detachments of artillery and engineers.<sup class="reference" id="cite_ref-18">[19] Meanwhile, Hube's XIV Panzer Corps was positioned to face possible landings from the sea with 16th Panzer Division in the Gulf of Salerno, the Hermann Göring Division near Naples and the 15th Panzergrenadier Division to the north in the Gulf of Gaeta.<sup class="reference" id="cite_ref-19">[20]

On 8 September (before the main invasion), the surrender of Italy to the Allies was announced, first by Eisenhower, then in the Badoglio Proclamation by the Italian government. Italian units ceased combat and the Navy sailed to Allied ports to surrender. The German forces in Italy were prepared for this and implemented Operation Achse to disarm Italian units and occupy important defensive positions.

Operation Slapstick commenced on 9 September. The first echelon of 1st Airborne arrived on four British cruisers, a US cruiser, and the British fast minelayer HMS Abdiel. The Italian battleships  Andrea Doria  and  Caio Duilio  with two cruisers passed by, en route to surrender in Malta. There were no Germans in Taranto and so disembarkation was unopposed. The only casualties occurred when Abdiel, at anchor, struck a mine and sank in minutes, with 168 killed and 126 injured.<sup class="reference" id="cite_ref-Molony243_20-0">[21] On 11 September, as patrols were sent further afield, there were some sharp encounters with elements of the German 1st Parachute Division. But 1st Parachute could do little but skirmish and fall back because most of its strength was attached to the 26th Panzer and Herman Göring Divisions at Salerno. 1st Airborne's commander, Major General George F. Hopkinson, was mortally wounded in one of these actions. By 11 September the ports of Bari and Brindisi were occupied.<sup class="reference" id="cite_ref-Molony243_20-1">[21]

Salerno landings
Operation Avalanche - the main invasion at Salerno by the U.S. 5th Army - began on 9 September, and in order to secure surprise, the Army decided to assault without preliminary naval or aerial bombardment. However, as amphibious force commander Hewitt had predicted, tactical surprise was not achieved. As the first wave of the U.S. 36th Infantry Division approached the shore at Paestum a loudspeaker from the landing area proclaimed in English: "Come on in and give up. We have you covered." The Allied troops attacked nonetheless.<sup class="reference" id="cite_ref-21">[22]

Major General Rudolf Sieckenius commander of 16th Panzer Division had organised his forces into four mixed arms battle groups which he had placed roughly 6 mi (9.7 km) apart and between 3 and 6 mi (4.8 and 9.7 km) back from the beaches. The Dőrnemann group was just east of Salerno (and therefore were opposite 46th Division when it landed), the Stempel battle group was between Pontecagnano and Battipaglia (and so faced the 56th Division), the Holtey battle group was in a reserve role at Persano on the Sele river which formed the corps boundary between X and VI Corps, while the von Doering battle group responsible for the Albanella to Rutino sector was 4 mi (6.4 km) south-east of Ogliastro, somewhat south of the 36th Division's beaches.<sup class="reference" id="cite_ref-22">[23]

X Corps, composed of the British 46th and 56th Divisions and a light infantry force of U.S. Rangers and British Commandos of Brigadier 'Lucky' Laycock's 2nd Special Service Brigade, experienced mixed reactions to its landings. The Rangers met no opposition and with support from the guns of HMS Ledbury seized their mountain pass objectives while the Commandos, from No. 2 Commando and No. 41 (Royal Marine) Commando, were also unopposed and secured the high ground on each side of the road through Molina Pass on the main route from Salerno to Naples. At first light units of No. 2 Commando moved towards Salerno and pushed back a small force of tanks and armoured cars from 16th Panzer Reconnaissance battalion.<sup class="reference" id="cite_ref-Molony280_23-0">[24]

The two British infantry divisions, however, met determined resistance and had to fight their way ashore with the help of naval bombardments. The depth and intensity of German resistance forced British commanders to concentrate their forces, rather than driving for a linkup with the Americans to the south.

At Paestum, the two lead battalions of the 36th (Texas) Division (from 141st and 142nd Regimental Combat Teams) received a hot reception from two companies of the von Doering group.<sup class="reference" id="cite_ref-Molony280_23-1">[24] The division had not been in combat before and as a result of the Italian surrender, there was a general belief amongst the soldiers that the landings would be routine.<sup class="reference" id="cite_ref-24">[25] 141st RCT lost cohesion and failed to gain any depth during the day which made the landing of supporting arms and stores impossible, leaving them without artillery and anti-tank guns.<sup class="reference" id="cite_ref-25">[26] However, 142nd RCT fared better and with the support of 143rd RCT, the reserve formation which had landed by 0800, were able to push forward.

By the end of the first day the 5th Army, although it had not gained all its objectives, had made a promising start: X Corps' two assault divisions had pushed between 5 and 7 mi (8.0 and 11 km) inland and the special forces had advanced north across the Sorrento Peninsula and were looking down on the Plain of Naples. To the south, 36th Division had established itself in the plain to the right of the Sele river and the higher ground to a depth of 5 mi (8.0 km), although 141st RCT was still stuck near the beach. However, XIV Panzer Corps commander Hermann Balck had seen the 16th Panzer Division's battle groups perform as intended and he had ordered both the Hermann Göring Division south to the battle and later in the day had been able to order 15th Panzergrenadier likewise. Meanwhile to the south, 29th Panzergrenadier Division from LXXVI Panzer Corps had also been directed to Salerno.<sup class="reference" id="cite_ref-26">[27] Neither side had gained the initiative.

Consolidation of the beachhead
For the next three days, the Allies fought to expand their beachhead while the Germans defended stubbornly to mask the build-up of their reinforcements for a counter-offensive.<sup class="reference" id="cite_ref-27">[28] On 10 September, Clark visited the battlefield and judged that it was unlikely that X Corps would be able to push quickly east past Battipaglia to link with VI corps. Since X Corps' main line of thrust was to be north towards Naples, he decided to move the VI Corps left hand boundary north of the Sele river and move the bulk of 45th Division into the gap. In view of the enemy reinforcements approaching from the north he also ordered a battalion-sized mixed arms group to reinforce the Rangers the next day.<sup class="reference" id="cite_ref-28">[29] Over the same period, German reinforcements filtered into the battlefield. Units, short of transport and subjected to other delays, arrived piecemeal and were formed into ad-hoc battle groups for immediate action. By 13 September, all the immediately available reinforcements had arrived including additional elements from 3rd Panzergrenadier Division which had been released by Kesselring from further north near Rome.<sup class="reference" id="cite_ref-29">[30] By contrast, the Allied build-up was constrained by the limited transport available for the operation and the pre-determined schedule of the build-up based on how, during the planning phase, it had been anticipated the battle would develop. By 12 September, it had become clear that 5th Army had an acute shortage of infantry on the ground.<sup class="reference" id="cite_ref-30">[31] On 12 September, General Alexander reported to London that: "I am not satisfied with the situation at Avalanche. The build-up is slow and they are pinned down to a bridgehead which has not enough depth. Everything is being done to push follow-up units and material to them. I expect heavy German counter-attack to be imminent."<sup class="reference" id="cite_ref-31">[32]

By 12 September, X Corps had taken a defensive posture because every battalion was committed and there were no reserves available to form an attack.<sup class="reference" id="cite_ref-32">[33] In the south, 36th Division made some progress but towards midday a counter-attack by elements of 29th Panzergrenadier Division overran 1st battalion 142nd Infantry.

German counterattacks
A German PAK near SalernoOn 13 September, the Germans launched their counteroffensive. While the Herman Göring battle groups attacked the northern flank of the beachhead, the main attack was on the boundary between the two Allied Corps which ran roughly from Battipaglia to the sea, with the greatest weight due to fall on the VI Corps side <sup class="reference" id="cite_ref-33">[34] On the morning of 13 September elements of 36th Division attacked and captured Altavilla in the high ground some 9 mi (14 km) behind Paestum but a counterattack forced them to withdraw as darkness fell. During the afternoon, two German battlegroups, the Kleine Limburg and the Krüger had attacked Persano and overrun 1st battalion 157th Infantry before crossing the Sele to engage 2nd battalion 143rd Infantry and virtually wipe it out.<sup class="reference" id="cite_ref-34">[35]

The battle groups continued their strike south and south-west until reaching the confluence of the Sele and its large tributary the Calore, where it was stopped by artillery firing over open sights, naval gunfire and a makeshift infantry position manned by artillerymen, drivers, cooks and clerks and anyone else that Walker, commander of 36th Division could scrape together.<sup class="reference" id="cite_ref-35">[36]

VI Corps had by this time lost the best part of three battalions and so the forward units of both its divisions were withdrawn to reduce the length of the defensive line. 45th Division consolidated at the Sele - Calore position while 36th Division was on the high ground on the seaward side of the La Caso stream (which flowed into the Calore).<sup class="reference" id="cite_ref-36">[37] The new perimeter was held with the assistance of the 82nd Airborne Division. Two battalions (1,300 paratroops) of the 504th Parachute Infantry Regiment, after the cancellation of Giant II, had been assigned to execute the final version of Operation Giant I at Capua on the evening of 13 September. Instead they jumped inside the beachhead, guided by transponding radar beacons and moved immediately into the line on the right of VI Corps. The next night, with the crisis passed, 2,100 troops of the 505th Parachute Infantry Regiment also parachuted into the beachhead and reinforced the 504th. A clear sign of the crisis passing was that when on the afternoon of 14 September, 180th infantry the final regiment of 45th Division landed, Clark was able to place it in reserve rather than in the line.<sup class="reference" id="cite_ref-37">[38] The 325th Glider Infantry Regiment, reinforced by the 3rd Battalion 504th PIR, landed by sea on 15 September. A night drop of 600 paratroops of the 2nd Battalion 509th Parachute Infantry to disrupt German movements behind the lines in the vicinity of Avellino was widely dispersed and failed,<sup class="reference" id="cite_ref-Molony322_38-0">[39] incurring significant casualties.

With strong naval gunfire support from the British Royal Navy and well-served by Fifth Army's artillery, the reinforced and reorganized infantry units defeated all German attempts on 14 September to find a weak spot in the lines. German losses, particularly in tanks, were severe. In addition, on 14 September and the following night Tedder ordered every available aircraft to support 5th Army, including the strategic bomber force. Over 1,000 tons of bombs were dropped during the daylight hours of that day.<sup class="reference" id="cite_ref-39">[40]

On 15 September 16th Panzer Division and 29th Panzergrenadier Division went on the defensive, thus marking the end to the thrust towards Paestum.<sup class="reference" id="cite_ref-40">[41] Further north the Schmalz group of the Hermann Göring Division achieved surprise attacking 128th Infantry Brigade on the high ground east of Salerno. The armoured column following up was intercepted and driven back leaving the German infantry exposed.<sup class="reference" id="cite_ref-41">[42]

The Allied bomber effort continued on 15 September, although slightly less intense than the previous day, as did the naval bombardment. The arrival of the British battleships HMS Warspite and  Valiant , with 15 in (38 cm) guns off the beaches provided the Allied troops with a morale boost, although Valiant was not required to shoot and Warspite ' s 29 rounds fired were awe-inspiring but a minor contribution to the naval 2,592 rounds fired in total that day.<sup class="reference" id="cite_ref-42">[43]

On 15 September, Kesselring reported to the High Command that the Allies air and naval superiority had forced LXXVI Panzer Corps onto the defensive and that a decisive success would depend on the current attack by XIV Panzer Corps. If this failed, Tenth Army must break off the battle to avoid being 'mangled'.<sup class="reference" id="cite_ref-43">[44]

On 16 September, the Schmalz group renewed its efforts on the X Corps front but with no more success. The airforce and navy continued to batter enemy targets, although during an air raid by fighters fitted with radio-controlled bombs, Warspite was hit and disabled which required her to be towed to Malta for repair.<sup class="reference" id="cite_ref-Molony322_38-1">[39]

Eighth Army ordered to apply pressure
On 9 September, Montgomery's formations had been strung out along the coastal roads in the 'toe' of Italy. The build-up across the Straits of Messina had proved slow and he was therefore short of transport. On 9 September, he decided to halt his formations in order to reorganise before pushing on but Alexander replied on 10 September that "It is of the utmost importance that you maintain pressure upon the Germans so that they cannot remove forces from your front and concentrate them against Avalanche". This message was further reinforced on 12 September by a personal visit from Alexander's Chief of Staff.<sup class="reference" id="cite_ref-44">[45] Montgomery had no choice and while reorganising the main body of his troops sent light forces up the coast which reached Castrovillari and Belvedere on 12 September, still some 80 mi (130 km) from the Salerno battlefield. On 14 September, he was in a position to start a more general advance, and by 16 September 5th Infantry Division had reached Sapri, 25 mi (40 km) beyond Belvedere, where forward patrols made contact with patrols from VI Corps' 36th Division.<sup class="reference" id="cite_ref-Molony246_45-0">[46]

German withdrawal
On 16 September, von Vietinghoff reported to Kesselring that the Allied air and naval superiority were decisive and that he had not the power to neutralize this. Tenth Army had succeeded in preventing troops being cut off, and continuing the battle would just invite heavy losses. The approach of Eighth Army was also now posing a threat. He recommended to break off the battle, pivoting on Salerno to form a defensive line, preparatory to commencing withdrawal on 18/19 September. Kesselring's agreement reached von Vietinghoff early on 17 September.<sup class="reference" id="cite_ref-46">[47]

Salerno mutiny
The Salerno battle was also the site of the Salerno Mutiny instigated by about 600 men of the British X Corps, who on 16 September refused assignment to new units as replacements. They had previously understood that they would be returning to their own units from which they had been separated during the fighting in the North African Campaign, mainly because they had been wounded. Eventually the corps commander, McCreery, persuaded most of the men to follow their orders. The NCOs who led the mutiny were sentenced to death but were eventually allowed to rejoin units and the sentence was not carried out.

Further Allied advances
Allied advance to the Volturno riverMap of the German prepared defensive lines south of RomeWith the Salerno beachhead secure, the Fifth Army began its attack northwest towards Naples on 19 September. The 82nd Airborne, after suffering serious casualties near Altavilla Silentina, was shifted to X Corps, joining the Rangers and the British 23rd Armoured Brigade on the Sorrento Peninsula to flank the German defenses at Nocera Inferiore, Sant'Antonio Abate and Angri, which the 46th (North Midland) Division attacked. The 7th Armoured Division, passing through the 46th Division, was assigned the task of taking Naples, while the newly landed U.S. 3rd Infantry Division took Acerno on 22 September and Avellino on 28 September.

The 8th Army had been making good progress from the "toe" in the face of German engineer actions and linked with the 1st Airborne Division on the Adriatic coast. It united the left of its front with the Fifth Army's right on 16 September and advancing up the Adriatic coast captured the airfields near Foggia on 27 September. Foggia was a major Allied objective because the large airfield complex there would give the Allied air forces the ability to strike new targets in France, Germany and the Balkans.

A Squadron of the King's Dragoon Guards entered Naples on 1 October (whose occupying forces had just been ejected by a popular uprising) and the entire Fifth Army, now consisting of three British and five U.S. divisions, reached the line of the Volturno River on 6 October. This provided a natural defensive barrier, securing Naples, the Campainian Plain and the vital airfields on it from German counterattack. Meanwhile, on the Adriatic coast, the British 8th Army had advanced to a line from Campobasso to Larino and Termoli on the Biferno river.

Aftermath
The German 10th Army had come close to defeating the Salerno beachhead. The stubborn initial resistance by 16th Panzer Division's battlegroups and the Germans' ability to reinforce them by land more quickly than the Allies could land follow-up forces by sea or air had almost tipped the battle. 5th Army planners had concentrated the main weight of its forces in X Corps on its left wing, in line with its major objective of advancing on Naples. This had left its right wing thinly manned to defend X Corps' right flank and left a particular weakness at the corps boundary.<sup class="reference" id="cite_ref-47">[48] In the end, the Germans, aware of the limited time available to deal with the Salerno landings because of the inevitable arrival in due course of Eighth Army, were obliged to make hurried and uncoordinated attempts to force a quick decision<sup class="reference" id="cite_ref-Molony246_45-1">[46] and had failed to break through Allied lines and exploit the gains in the face of total Allied air superiority and artillery and naval gunfire support. The Allies had been fortunate that at this time Adolf Hitler had sided with the view of his Army Group commander in Northern Italy, Field Marshal Erwin Rommel, and decided that defending Italy south of Rome was not a strategic priority. As a result, Kesselring had been forbidden to call upon reserves from the northern Army Group.

The success of the 10th Army in inflicting heavy casualties, and Kesselring's strategic arguments, led Hitler to agree that the Allies should be kept away from German borders and prevented from gaining the oil resources of the Balkans. On 6 November,<sup class="reference" id="cite_ref-48">[49] Hitler withdrew Rommel to oversee the build-up of defenses in northern France and gave Kesselring command of the whole of Italy with a remit to keep Rome in German hands for as long as possible.<sup class="reference" id="cite_ref-49">[50]

By early October, the whole of southern Italy was in Allied hands, and the Allied armies stood facing the Volturno Line, the first of a series of prepared defensive lines running across Italy from which the Germans chose to fight delaying actions, giving ground slowly and buying time to complete their preparation of the Winter Line, their strongest defensive line south of Rome. The next stage of the Italian Campaign became for the Allied armies a grinding and attritional slog against skillful, determined and well-prepared defenses in terrain and weather conditions which favoured defense and hampered the Allied advantages in mechanised equipment and air superiority. It took until mid-January 1944 to fight through the Volturno, Barbara and Bernhardt lines to reach the Gustav Line, the backbone of the Winter Line defenses, setting the scene for the four battles of Monte Cassino which took place between January and May 1944.

Clark's award
General Mark W. Clark was awarded the Distinguished Service Cross, the second-highest U.S. award for valor in combat, for his front-line leadership during this crisis. He was frequently seen in the most forward positions encouraging the troops. However, in the opinion of historian Carlo D'Este,<sup class="Template-Fact" style="white-space: nowrap;">[citation needed] Clark's poor planning of the operation caused the crisis in the first place. Clark himself blamed the slowness of the Eighth Army for the beachhead crisis, for which there was at least some validity<sup class="Template-Fact" style="white-space: nowrap;">[citation needed].