World War II: Invasion of Italy

Allied troops landing in Italy, 1943
US forces land at Salerno, September 1943. Photograph Courtesy of the US Naval History & Heritage Command

The Allied invasion of Italy took place September 3–16, 1943, during World War II (1939–1945). Having driven the German and Italian troops from North Africa and Sicily, the Allies decided to invade Italy in September 1943. Landing in Calabria and south of Salerno, British and American forces pushed inland. The fighting around Salerno proved particularly fierce and ended when British forces from Calabria arrived. Defeated around the beaches, the Germans withdrew north to the Volturno Line. The invasion opened a second front in Europe and helped take pressure off Soviet forces in the east.

Fast Facts: Invasion of Italy


With the conclusion of the campaign in North Africa in the late spring of 1943, Allied planners began looking north across the Mediterranean. Though American leaders such as General George C. Marshall favored moving forward with an invasion of France, his British counterparts desired a strike against southern Europe. Prime Minister Winston Churchill ardently advocated for attacking through what he termed "the soft underbelly of Europe," as he believed that Italy could be knocked out of the war and the Mediterranean opened to Allied shipping.  

As it became increasingly clear that resources were not available for a cross-Channel operation in 1943, President Franklin Roosevelt agreed to the invasion of Sicily. Landing in July, American and British forces came ashore near Gela and south of Syracuse. Pushing inland, the troops of Lieutenant General George S. Patton's Seventh Army and General Sir Bernard Montgomery's Eighth Army pushed back the Axis defenders. 

Next Steps

These efforts resulted in a successful campaign that led to the overthrow of Italian leader Benito Mussolini in late July 1943. With operations in Sicily coming to close in mid-August, the Allied leadership renewed discussions regarding an invasion of Italy. Though the Americans remained reluctant, Roosevelt understood the need to continue engaging the enemy to relieve Axis pressure on the Soviet Union until landings in northwest Europe could move forward. Also, as the Italians had approached the Allies with peace overtures, it was hoped that much of the country could be occupied before German troops arrived in large numbers.

Prior to the campaign in Sicily, Allied plans foresaw a limited invasion of Italy that would be restricted to the southern part of the peninsula. With the collapse of Mussolini's government, more ambitious operations were considered. In assessing options for invading Italy, the Americans initially hoped to come ashore in the northern part of the country, but the range of Allied fighters limited potential landing areas to the Volturno river basin and the beaches around Salerno. Though further south, Salerno was chosen due to its calmer surf conditions, proximity to Allied air bases, and the existing road network beyond the beaches.

Operation Baytown

Planning for the invasion fell to Supreme Allied Commander in the Mediterranean, General Dwight D. Eisenhower, and the commander of the 15th Army Group, General Sir Harold Alexander. Working on a compressed schedule, their staffs at Allied Force Headquarters devised two operations, Baytown and Avalanche, which called for landings in Calabria and Salerno, respectively. Assigned to Montgomery's Eighth Army, Baytown was scheduled for September 3.

It was hoped that these landings would draw German forces south, allowing them to be trapped in southern Italy by the later Avalanche landings on September 9. This approach also had the benefit of the landing craft being able to depart directly from Sicily. Not believing that the Germans would give battle in Calabria, Montgomery came to oppose Operation Baytown as he felt that it placed his men too far from the main landings at Salerno. As events unfolded, Montgomery was proved correct, and his men were forced to march 300 miles against minimal resistance to the reach the fighting.

Operation Avalanche

Execution of Operation Avalanche fell to Lieutenant General Mark Clark's U.S. Fifth Army, which was comprised of Major General Ernest Dawley's U.S. VI Corps and Lieutenant General Richard McCreery's British X Corps. Tasked with seizing Naples and driving across to the east coast to cut off enemy forces to the south, Operation Avalanche called for landing on a broad, 35-mile front to the south of Salerno. Responsibility for the initial landings fell to the British 46th and 56th Divisions in the north and the U.S. 36th Infantry Division in the south. The Sele River separated the British and American positions.

Supporting the invasion's left flank was a force of U.S. Army Rangers and British Commandos, which were given the objective of securing the mountain passes on the Sorrento Peninsula and blocking German reinforcements from Naples. Prior to the invasion, extensive thought was given to a variety of supporting airborne operations utilizing the U.S. 82nd Airborne Division. These included employing glider troops to secure the passes on the Sorrento Peninsula as well as a full-division effort to capture the crossings over the Volturno River.

Each of these operations was deemed either unnecessary or unsupportable and was dismissed. As a result, the 82nd was placed in reserve. At sea, the invasion would be supported by a total of 627 vessels under the command of Vice Admiral Henry K. Hewitt, a veteran of both the North Africa and Sicily landings. Though achieving surprise was unlikely, Clark made no provision for a pre-invasion naval bombardment despite evidence from the Pacific that suggested this was required.

German Preparations

With the collapse of Italy, the Germans commenced plans for defending the peninsula. In the north, Army Group B, under Field Marshal Erwin Rommel, assumed responsibility as far south as Pisa. Below this point, Field Marshal Albert Kesselring's Army Command South was tasked with halting the Allies. Kesselring's primary field formation, Colonel General Heinrich von Vietinghoff's Tenth Army, consisting of XIV Panzer Corps and LXXVI Panzer Corps, came online on August 22 and began moving to defensive positions. Not believing that any enemy landings in Calabria or other areas in the south would be the main Allied effort, Kesselring left these areas lightly defended and directed troops to delay any advances by destroying bridges and blocking roads. This task largely fell to General Traugott Herr's LXXVI Panzer Corps.

Montgomery Lands

On September 3, Eighth Army's XIII Corps crossed the Straits of Messina and commenced landings at various points in Calabria. Meeting light Italian opposition, Montgomery's men had little trouble coming ashore and began forming to move north. Though they encountered some German resistance, the greatest impediment to their advance came in the form of demolished bridges, mines, and roadblocks. Due to the rugged nature of the terrain, which held British forces to the roads, Montgomery's speed became dependent on the rate at which his engineers could clear obstacles.

On September 8, the Allies announced that Italy had formally surrendered. In response, the Germans initiated Operation Achse, which saw them disarm Italian units and take over the defense of key points. With the Italian capitulation, the Allies commenced Operation Slapstick on September 9, which called for British and U.S. warships to ferry the British 1st Airborne Division into the port of Taranto. Meeting no opposition, they landed and occupied the port.

Landing at Salerno

On September 9, Clark's forces began moving towards the beaches south of Salerno. Aware of the Allies' approach, German forces on the heights behind the beaches prepared for the landings. On the Allied left, the Rangers and Commandos came ashore without incident and quickly secured their objectives in the mountains of the Sorrento Peninsula. To their right, McCreery's corps encountered fierce German resistance and required naval gunfire support to move inland. Fully occupied on their front, the British were unable to press south to link up with the Americans.

Meeting intense fire from elements of the 16th Panzer Division, the 36th Infantry Division initially struggled to gain ground until reserve units were landed. As night fell, the British had achieved an advance inland of between five to seven miles while the Americans held the plain to the south of the Sele and gained around five miles in some areas. Though the Allies had come ashore, German commanders were pleased with the initial defense and began shifting units towards the beachhead.

The Germans Strike Back

Over the next three days, Clark worked to land additional troops and expand the Allied lines. Due to the tenacious German defense, growing the beachhead proved slow, which hampered Clark's ability to build up additional forces. As a result, by September 12, X Corps switched to the defensive as insufficient men were available to continue the advance. The next day, Kesselring and von Vietinghoff commenced a counteroffensive against the Allied position. While the Hermann Göring Panzer Division struck from the north, the main German attack hit the boundary between the two Allied corps.

This assault gained ground until stopped by a last-ditch defense by the 36th Infantry Division. That night, the U.S. VI Corps was reinforced by elements of the 82nd Airborne Division, which jumped inside the Allied lines. As additional reinforcements arrived, Clark's men were able to turn back German attacks on September 14 with the aid of naval gunfire. On September 15, having sustained heavy losses and failed to break through the Allied lines, Kesselring put the 16th Panzer Division and 29th Panzergrenadier Division on the defensive. To the north, XIV Panzer Corps continued their attacks but were defeated by Allied forces supported by airpower and naval gunfire.

Subsequent efforts met a similar fate the next day. With the battle at Salerno raging, Montgomery was pressed by Alexander to hasten Eighth Army's advance north. Still hampered by poor road conditions, Montgomery dispatched light forces up the coast. On September 16, forward patrols from this detachment made contact with the 36th Infantry Division. With Eighth Army's approach and lacking the forces to continue attacking, von Vietinghoff recommended breaking off the battle and pivoting Tenth Army into a new defensive line spanning the peninsula. Kesselring agreed on September 17 and on the night of the 18/19th, German forces began pulling back from the beachhead.


During the course of the invasion of Italy, Allied forces sustained 2,009 killed, 7,050 wounded, and 3,501 missing while German casualties numbered around 3,500. Having secured the beachhead, Clark turned north and began attacking towards Naples on September 19. Arriving from Calabria, Montgomery's Eighth Army fell into line on the east side of the Apennine Mountains and pushed up the east coast.

On October 1, Allied forces entered Naples as von Vietinghoff's men withdrew into the positions of the Volturno Line. Driving north, the Allies broke through this position and the Germans fought several rearguard actions as they retreated. Pursuing, Alexander's forces ground their way north until encountering the Winter Line in mid-November. Blocked by these defenses, the Allies finally broke through in May 1944 following the Battles of Anzio and Monte Cassino.


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Hickman, Kennedy. "World War II: Invasion of Italy." ThoughtCo, Apr. 5, 2023, Hickman, Kennedy. (2023, April 5). World War II: Invasion of Italy. Retrieved from Hickman, Kennedy. "World War II: Invasion of Italy." ThoughtCo. (accessed June 4, 2023).