The Falklands War (link=no or Guerra del Atlántico Sur), also known as the Falklands Conflict or Falklands Crisis, was a 1982 war between Argentina and the United Kingdom. The conflict resulted from the long-standing dispute over the sovereignty of the Falkland Islands and South Georgia and the South Sandwich Islands, which lie in the South Atlantic, east of Argentina.

The Falklands War began on Friday 2 April 1982, when Argentine forces invaded and occupied the Falkland Islands and South Georgia. The British government dispatched a naval task force to engage the Argentine Navy and Air Force, and retake the islands by amphibious assault.
The resulting conflict lasted 74 days and ended with the Argentine surrender on 14 June 1982, which returned the islands to British control. During the conflict, 649 Argentine military personnel, 255 British military personnel and 3 Falkland Islanders died.

The conflict was the result of a protracted historical confrontation regarding the sovereignty of the islands. Argentina has asserted that the Falkland Islands have been Argentinian territory since the 19th century and, shows no sign of relinquishing the claim. The claim was added to the Argentine constitution after its reformation in 1994. As such, the Argentine government characterised their initial invasion as the re-occupation of their own territory, whilst the British government saw it as an invasion of a British dependent territory.
However, neither state officially declared war and hostilities were almost exclusively limited to the territories under dispute and the local area of the South Atlantic.

The conflict had a strong impact in both countries. Patriotic sentiment ran high in Argentina, but the outcome prompted large protests against the ruling military government, which hastened its downfall. In the United Kingdom, Prime Minister Margaret Thatcher's government was bolstered by the successful outcome.
The war has played an important role in the culture of both countries, and has been the subject of several books, scholarly articles, films, and songs.
Over time, the cultural and political weight of the conflict has had less effect on the British public than on that of Argentina, where the war is still a topic of discussion.

Relations between the United Kingdom and Argentina were restored in 1989 following a meeting in Madrid, at which the two Governments issued a joint statement which explicitly did not change either side's position on sovereignty.