The amphibious Battle of Gela was the opening engagement of the American portion of the Allied Invasion of Sicily during World War II. United States Navy ships landed United States Army troops along the eastern end of the south coast of Sicily; and withstood attacks by Luftwaffe and Regia Aeronautica aircraft while defending the beachhead against German tanks and Italian tanks of the Livorno Division until the Army captured the Ponte Olivo Airfield for use by United States Army Air Forces planes. The battle convinced United States Army officers of the value of naval artillery support, and revealed problems coordinating air support from autonomous air forces during amphibious operations.

The Allied invasion of Sicily, codenamed Operation Husky, was a major campaign of World War II, in which the Allies took the island of Sicily from the Axis powers (Fascist Italy and Nazi Germany). It began with a large amphibious and airborne operation, followed by a six-week land campaign, and initiated the Italian Campaign.

To divert some of the Axis forces to other areas, the Allies engaged in several deception operations, the most famous and successful of which was Operation Mincemeat. Husky began on the night of 9–10 July 1943, and ended on 17 August. Strategically, Husky achieved the goals set out for it by Allied planners; the Allies drove Axis air, land and naval forces from the island and the Mediterranean sea lanes were opened for Allied merchant ships for the first time since 1941. The Italian leader, Benito Mussolini, was toppled from power in Italy and the way was opened for the Allied invasion of Italy. The German leader, Adolf Hitler, "canceled a major offensive at Kursk after only a week, in part to divert forces to Italy", resulting in a reduction of German strength on the Eastern Front. The collapse of Italy necessitated German troops replacing the Italians in Italy and to a lesser extent the Balkans, resulting in one fifth of the entire German army being diverted from the east to southern Europe, a proportion that would remain until near the end of the war.