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(Saturday, January 22, 1944, 2:00 a.m. Central European Time; part of the Winter Line and the battle for Rome of the Italian Campaign of World War II) — Operation Shingle, the landings at Anzio, began early this morning with an Allied amphibious landing in the region of Anzio and Nettuno, with the objective of outflanking German forces at the Winter Line and setting up a drive on Rome.

The operation was initially commanded by Major General John P. Lucas, of the U.S. Army, commanding U.S. VI Corps with the intent to outflank German forces at the Winter Line and enable an attack on Rome.

The success of an amphibious landing at that location, in a basin consisting substantially of reclaimed marshland and surrounded by mountains, depended on the element of surprise and the swiftness with which the invaders could build up strength and move inland relative to the reaction time and strength of the defenders.

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Any delay could result in the occupation of the mountains by the defenders and the consequent entrapment of the invaders. Lieutenant General Mark W. Clark, commander of the U.S. Fifth Army, understood that risk, but he did not pass on his appreciation of the situation to his subordinate Lucas, who preferred to take time to entrench against an expected counterattack.

The initial landing achieved complete surprise with no opposition and a jeep patrol even made it as far as the outskirts of Rome. However, Lucas, who had little confidence in the operation as planned, failed to capitalize on the element of surprise and delayed his advance until he judged his position was sufficiently consolidated and he had sufficient strength.

While Lucas consolidated, Field Marshal Albert Kesselring, the German commander in the Italian theatre, moved every unit he could spare into a defensive ring around the beachhead. His artillery units had a clear view of every Allied position.

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The Germans also stopped the drainage pumps and flooded the reclaimed marsh with salt water, planning to entrap the Allies and destroy them by epidemic. For weeks a rain of shells fell on the beach, the marsh, the harbour, and on anything else observable from the hills, with little distinction between forward and rear positions.

After a month of heavy but inconclusive fighting, Lucas was relieved and sent home. His replacement was Major General Lucian Truscott, who had previously commanded the U.S. 3rd Infantry Division.

The Allies broke out in May. But, instead of striking inland to cut lines of communication of the German Tenth Army’s units fighting at Monte Cassino, Truscott, on Clark’s orders, reluctantly turned his forces north-west towards Rome, which was captured on June 4, 1944.

As a result, the forces of the German Tenth Army fighting at Cassino were able to withdraw and rejoin the rest of Kesselring’s forces north of Rome, regroup, and make a fighting withdrawal to his next major prepared defensive position on the Gothic Line.