The Battle of Madagascar was the British campaign to capture Vichy French-controlled Madagascar during World War II. The seizure of the island by the British was to deny Madagascar's ports to the Imperial Japanese Navy and to prevent the loss or impairment of the Allied shipping line. It began with Operation Ironclad, the seizure of the port of Diego Suarez near the northern tip of the island, on 5 May 1942.
A subsequent campaign to secure the entire island, Operation Stream Line Jane, was opened on 10 September. The Allies broke into the interior linking up with forces on the coast and secured the island by the end of October. Fighting ceased and an armistice was granted on 6 November. This was the first large scale operation by the Allies of World War II combining sea, land and air forces.