The battle of Elba (17-19 June 1944) saw a largely French force capture the island after overwhelming a much smaller Italian and German garrison (Italian Campaign).
As the Allies advanced up the west coast of Italy in the aftermath of the fall of Rome, the US Fifth Army approached Elba. Allied Intelligence believed that there were 5,000 Italian fascist and 2,000 German soldiers on the island, and it was decided to carry out a large scale landing on the island, which would otherwise pose a potential threat to the Allied rear areas as the armies moved further north.
The landing was carried out by two regimental combat teams from the French 9th Colonial Division, a command battalion and a group of North African goumiers, a total of 9,700 French troops. They were supported by a Royal Navy task force and by American aircraft. The expedition was launched from Corsica, just over 30 miles to the west of Elba, rather than from the Italian mainland, only 5 miles to the east, as Corsica had been in Allied hands for some time by the summer of 1944.
The French landed early on 17 June, after an easy crossing. The garrison turned out to be much smaller than expected - 2,500 strong, with nearly 2,000 Germans and only 550 Italian fascists. The defenders attempted to defend the shoreline, but the French were able to create two beachhead.
Once the French were ashore, Axis resistance quickly crumbled. Most of the fighting was over by the end of 18 June, and the island was secured by 19 June.
The conquest of Elba worried the Germans, who were constantly aware that the Allies could carry out more amphibious landings behind their lines. As a result Kesselring kept his main reserve, the 16th Panzer Grenadier Division, out of the front line for some time, and then introduced it one regiment at a time, leaving the bulk of the division around Livorno for longer than he needed to.