Battle of Anzio
Battle of Anzio, (January 22–June 5, 1944) World War II battle, fought during the Italian Campaign. Some 50,000 Allied troops staged an amphibious landing (codenamed Operation Shingle) at Anzio, 33 miles (53 km) south of Rome, in an effort to bypass the strong German defenses along the Gustav Line.
From Sicily to the invasion of southern Italy
After their successful operations in North Africa and Sicily, the Allies had a wide choice of directions for their next offensive. Calabria, the “toe” of Italy, was a short distance from Allied armies in Sicily and most obvious possible destination, the “shin” was also vulnerable, and the “heel” was also very attractive. The two army corps of Montgomery’s Eighth Army crossed the Strait of Messina and landed on the “toe” of Italy on September 3, 1943. Although the initial resistance was practically negligible, they made only very slow progress, as the terrain, with only two good roads running up the coasts of the great Calabrian “toe” prevented the deployment of large forces. On the day of the landing, however, the Italian government agreed to the Allies’ secret terms for a capitulation. It was understood that Italy would be treated with leniency in direct proportion to the part that it would take, as soon as possible, in the war against Germany. The Italian surrender was announced on September 8.
The landing on the “shin” of Italy, at Salerno, just south of Naples, was begun on September 9, by the mixed U.S.–British Fifth Army, under U.S. Gen. Mark Clark. Transported by 700 ships, 55,000 troops made the initial assault, and 115,000 more followed up. At first they were faced only by the German 16th Panzer Division. Although German commander Field Marshal Albert Kesselring had only eight weak divisions to defend all of southern and central Italy, he had had time to plan since the overthrow of Italian dictator Benito Mussolini in July 1943. Kesselring had been expecting a blow at the “shin,” and his counterstroke made the success of the Salerno landing precarious for six days. It was not until October 1 that the Fifth Army entered Naples.
By contrast, the much smaller landing on the “heel” of Italy, which had been made on September 2 (the day preceding the invasion of the “toe”), took the Germans by surprise. Notwithstanding the paucity of its strength in men and in equipment, the expedition captured two good ports, Taranto and Brindisi, in a very short time, but it lacked the resources to advance promptly. Nearly a fortnight passed before another small force was landed at Bari, the next considerable port north of Brindisi, to push thence unopposed into Foggia.
It was the threat to their rear from the “heel” of Italy and from Foggia that had induced the Germans to fall back from their positions defending Naples against the Fifth Army. When the Italian government declared war against Germany on October 13, Kesselring was already receiving reinforcements and consolidating the German hold on central and northern Italy. The Fifth Army was checked temporarily on the Volturno River, only 20 miles (32 km) north of Naples, then more lastingly on the Garigliano River, while the Eighth Army, having made its way from Calabria up the Adriatic coast, was likewise held on the Sangro River. Autumn and midwinter passed without the Allies making any notable impression on the Germans’ Gustav Line, which ran for 100 miles (160 km) from the mouth of the Garigliano through Cassino and over the Apennines to the mouth of the Sangro.
The Anzio landings and the fall of Rome
British Prime Minister Winston Churchill had argued that Italy was the soft underbelly of Hitler’s Fortress Europe. While the Italian people had surrendered within days of the Allied landings, Italy’s terrain was much less accommodating. By the end of 1943, the Allies had advanced only 70 miles (113 km) beyond Salerno in four months of difficult fighting. Most of that ground had been gained during September, and thereafter the rate of progress became so gradual that it recalled the attrition warfare of World War I.
Such grinding tactics sometimes succeeded, but far more often resulted in disappointment and high casualties. The Italian Campaign was no exception to this rule, and it repeatedly demonstrated that direct attack on narrow fronts commonly resulted in negative outcomes. Even a significant superiority of force rarely suffices unless there is room for maneuver, which requires a relatively wider front. The Italian peninsula is barely 100 miles (160 km) wide, and most of that space is filled with the spine of the Apennines and its ribs. Once the German Supreme Command had decided that it would not cede Italy to the Allies, the establishment of a reasonable defensive density was bound to produce strategic cramp in the Allied advance up the leg of Italy.
Having experienced a measure of success with previous amphibious operations in the Mediterranean, early in 1944 the Allies determined to launch a fresh seaborne maneuver against the long coastline in the enemy’s rear. To divert attention from the landings—and with the hope of breaching the Gustav Line and launching a unified drive on Rome—the Fifth Army mounted a series of local offensives. The British X Corps on January 17 gained a bridgehead over the Garigliano but made no further progress. The U.S. II Corps (36th Division) on January 20–21 unsuccessfully attempted to force the rain-swelled Rapido. The Americans were facing the 15th Panzer Grenadier Division, one of the best German formations fighting in Italy, and the river crossing was a disaster. Hundreds of Americans were killed or wounded, and nearly 1,000 were captured when they were stranded on the German side of the Rapido.
On January 22 the Allied VI Corps landed on the beaches near Anzio, 33 miles (53 km) south of Rome. The assault force included the U.S. 3rd Division, British 1st Division, and U.S. Rangers. In 24 hours the Allies landed 36,000 troops and 3,000 vehicles and took control of Anzio and the neighbouring town of Nettuno. Only two German battalions were present in the area, and a swift dash inland could have seized the Alban Hills—covering the immediate approach to Rome—or even Rome itself. However, the Allies’ plan had been based on the calculation that the Germans would immediately counter the landing. Thus, they were primarily concerned with consolidating the beachhead, while the main forces in the south were to take advantage of the anticipated weakening of the enemy’s resistance there. The Germans did not react in the way expected.
When the lack of opposition near Anzio became clear, Gen. Harold Alexander, head of the Anglo-American Fifteenth Army Group, wished to quicken the move inland. VI Corps commander Gen. John P. Lucas opted for a more cautious approach, however, and no serious advance was attempted for more than a week. This allowed Kesselring ample time to switch his reserves to the scene, while he also held in check the forward drive of the main Allied forces on the Cassino sector. By the end of January, the VI Corps had been sealed in. On February 3, the 12th day after the landing, the Germans developed a powerful counteroffensive against the Allied position at Anzio. This in turn was checked, but the Allied force was left in an awkwardly shallow and narrow bridgehead.
Over the next four months, the Germans were able to deliver persistent and accurate artillery fire throughout the flat beachhead—18 miles (29 km) long by 9 miles (14.5 km) deep—and against ships offshore. The Luftwaffe also struck Allied positions and warships; some of the larger vessels were forced to move away from the shore, reducing the amount of naval gun support that could be delivered to the Anzio lodgment. Axis counterattacks reached the peak of their intensity on February 17, but the beachhead was held. During the four months of its existence, the beachhead was reinforced by the U.S. 1st Armoured, 34th, 36th, and 45th divisions and by the British 5th and 56th—the last being later withdrawn.
The bloody stalemate on the Gustav Line continued through most of spring 1944, but, in May of that year, the Allies planned to renew the offensive in Italy in a decisive fashion. The first phase of Alexander’s operation comprised a fresh attack on either side of Cassino, where previous offensives had been blocked. To intensify its effect, the Eighth Army, now commanded by Gen. Oliver Leese, shifted its weight from the Adriatic to join with Gen. Mark Clark’s Fifth Army in a combined blow against the western sector of the Gustav Line. Wedges were driven into the Gustav Line at a number of points between Cassino and the sea. The most significant penetration was made by Gen. Alphonse Juin’s Free French Colonial Corps, which exploited its specialized skill in mountain warfare to pursue a difficult route across the Aurunci Mountains. In three days Juin’s corps reached the heights overlooking the Liri valley and created a leverage that loosened the German hold on the Gustav Line. The threat eased the way both for the British to press up the valley and to outflank Cassino, which on May 18 fell to a Polish corps of the Eighth Army, and also for the Americans to push up the coast.
On May 23, 1944, the Allied force at Anzio struck out from the bridgehead. There the Germans had reduced their presence in order to send reinforcements to the south, and the Allied move was timed to exploit the weakening. On the third day the German defense cracked. Once the breakout was achieved, the Germans were short of reserves to meet the Allied follow-through toward the Alban Hills. Simultaneously with the Anzio stroke, the Eighth Army launched an assault on the Germans’ final position in the Liri valley, which the Canadian Corps dislodged on the first day. The next day it became clear that the Germans were falling back everywhere. Their retreat was soon accelerated, as the menace from Anzio developed.
Within a few days the direct line of retreat on Rome up Highway 6 was blocked, and the Germans were compelled to fork northeastward up difficult mountain roads, where their retreating columns were more exposed to a hammering from the air. A considerable part of the imperiled army managed to escape from the trap by this branching move, but its chance of covering Rome was forfeited. Alexander now switched all possible strength to his left wing against the other German army and, in a week of tough fighting, loosened its grip on the Alban Hills. Once this strategic breakwater collapsed, the Allied forces quickly flooded the flat country around Rome, capturing the city early on June 5. They had gained the prize which had been so nearly within their grasp nine months earlier, when the Italian government capitulated.
Casualties and significance
The Battle of Anzio cost the Americans nearly 24,000 combat casualties and the British nearly 10,000. The Allies also suffered 37,000 noncombat casualties, an unusually high number for an engagement in the European theatre. Many of these non-battlefield losses were caused by malaria and other mosquito-borne diseases that were endemic to the marshes in the beachhead area. The Germans suffered some 27,500 casualties.
From a tactical standpoint, the Anzio landings were clearly a failure. While the VI Corps succeeded in outflanking the Gustav Line, the decision to delay the advance on Rome played to Kesselring’s defensive strengths. As a result, the Allied forces were pinned in the bridgehead for four months. Within the strategy of the Italian Campaign and the overall Allied assault on Fortress Europe, however, the Anzio beachhead represented a threat that German commanders could not ignore. As a result, the 135,000 troops of the German Fourteenth Army were locked down south of Rome at a time when they could have been deployed against advancing Soviet forces on the Eastern Front.