The Argentinian government had claimed the Falkland Islands (Islas Malvinas) since Argentina achieved independence from the Spanish in the early 19th century. The islands themselves were claimed by the British in 1837 and Argentine claims were rejected. Since then, despite the wish of the FCO to relieve themselves of this minor problem, the 1,800 or so inhabitants (Kelpers) steadfastly refused to become part of Argentina, using Article 73 of the UN charter to support their position. In 1965 UN Resolution 2065 started negotiations between Britain and Argentina, but seventeen years later little had changed on the Falklands.
In Argentina however the government since 1976 had been another tough military junta, facing down both severe economic problems and leftist guerillas, the Montoneros. A very messy victory against the guerillas was achieved in 1981 but the economy was in an appalling state (140% inflation a month) as General Leopoldo Fortunato Galtieri came to power in the junta in January 1982.
Galtieri wanted to balanced the necessary but unpleasant economic reforms with a speedy nationalist 'win' over the Falklands. Pressure was exerted in the UN with a subtle hint of invasion raised, the British missed this threat and continued to time-waste. The Argetinians interpreted the British position as disengagement, being willing to step away if the islands were invaded, a view-pointed aided by the withdrawal of the last Royal Navy presence in 1981 (together with a general down-sizing of the fleet) and the British Nationally Bill of 1981 which withdrew full citizenship rights from the Kelpers. The British also helped by being unwilling to believe that the Argentines would invade.
The invasion plan was developed by Admiral Anaya, the passionately anti-British head of the navy. Following the failure of further talks in January 1982 the plans were finalised and the invasion set for April. The attack was pre-empted by the 'invasion' of the island of South Georgia (800 miles east of the Falklands) on March 19 by a group of patriotic Argentine civilians. HMS Endurance was ordered to remove any remaining civilians on March 25, but was blocked by three Argentine warships and wisely retreated. However on March 30 despite further evidence with the Argentine navy loading troops in Puerto Belgrano the JIC's Latin American group stated that "invasion was not imminent".
On April 2 Argentine Marines landed at Mullet Creek on the coast of East Falkland from where they advanced on Stanley. By 08.30 the battle was over, the Governor had ordered his ten Royal Marines (Navy Party 8901) to surrender. The Royal Marines, the Governor and any others who wished to were shipped out to Britain.
In Buenos Aires huge flag-waving crowds flooded the Plaza de Mayo on hearing the news. In London the government was in more of a state of shock on "Black Friday". The next day Argentinian forces seized the islands of South Georgia and South Sandwich, 1500 km to the east of the Falklands.
The British were quick to organise diplomatic pressure against Argentina and to organise a task force to dispatch to the islands, centred around the aircraft carriers HMS Invincible and HMS Hermes. On April 3 the UN passed a resolution calling for the withdrawal of Argentine troops from the islands and the cessation of hostilities. On April 10 the EEC approved trade sanctions against Argentina. Alexander Haig, the US secretary of State, briefly (8-30 April) headed a "shuttle diplomacy" mission before President Ronald Reagan declared US support for Britain and instituted sanctions against Argentina. The British declared a 'war exclusion zone' of 320 km around the Falklands.
There were some early clashes. The British easily retook South Georgia on April 25, Thatcher telling the media to "rejoice, rejoice", and aircraft flying from Ascension Island bombed the airfield at Port Stanley on May 1. On May 2 the aged Argentine cruiser General Belgrano was sunk by the British submarine HMS Conqueror with the loss of 321 lives (The Sun newspaper initially greeted this with the headline GOTCHA!). This loss hardened the stance of the Argentine government. Two days after the Belgrano sinking the British lost the Type 42 destroyer HMS Sheffield to fire following an Exocet missile strike.
The tempo of operations increased throughout May with UN attempts to mediate a peace being rejected by the British. On May 21 British forces made an amphibious landing near Port San Carlos, on the northern coast of East Falkland, putting 4000 men ashore. From the plan was to advance southward to capture Darwin and Goose Green before turning towards Port Stanley. At sea the paucity of British ships AA defences was again demonstrated in the sinking of HMS Ardent on the 21st, HMS Antelope on the 23rd, and MV Atlantic Conveyor on the 25th, HMS Coventry, HMS Argonaut and HMS Brilliant were badly damaged. The Argentines lost over thirty aircraft in these assaults
On May 28 British forces took Darwin and Goose Green after a tough struggle, seventeen British and 200 Argentine soldiers were killed and 1400 Argentine troops were made prisoners. By June 1 with a further 5000 British troops landed at San Carlos, Port Stanley was surrounded. The Argentine air assaults continued with fifty killed on Sir Galahad and Sir Tristam on June 8. June 12 was another day of bloody combat - on Mount Longdon thirty British and fifty Argentinian troops die, Mount Tumbledown is captured at the cost of fifty lives and Two Sisters and Mount Harriet are also captured, with a further thirteen killed when HMS Glamorgan is struck by an Exocet.
On June 14 the Argentine garrison in Port Stanley was defeated. The Argentine commander Mario Menendez agreed to surrender and 9800 Argentine troops are made POWs. On June 20 the British retake the South Sandwich Islands and declare the hostilities are at an end.
The conflict lasted 72 days, with 236 British and around 700 Argentine troops killed.
Politically the war was a massive boost to the popularity of Margaret Thatcher and played a role in ensuring her re-election in 1983. Conversely Galtieri was quick to resign, paving the way for the restoration of democracy in Argentina.