From Wikipedia

 The Falklands Conflict

 The Falklands War started on Friday, 2 April 1982, with the Argentine invasion and occupation of the Falkland Islands and South Georgia. Britain launched a naval task force to engage the Argentine Navy and Argentine Air Force, and retake the islands by amphibious assault. The conflict ended with the Argentine surrender on 14 June 1982, and the islands remained under British control. The war lasted 74 days. It resulted in the deaths of 257 British and 649 Argentine soldiers, sailors, and airmen, and the deaths of 3 civilian Falkland Islanders. It is the most recent external conflict to be fought by the UK without any allied states and the only external Argentine war since the 1880s.