The garrison defending the Falklands was Naval Party 8901 - a Royal Marine detachment that happened to be at double strength, because the unit was mid-handover and both the outgoing and incoming troops were on the islands at once. Even so, the numbers were hopeless. Major Mike Norman took command, Major Gary Noott advised the governor, and their force was thickened by sailors from the survey ship Endurance and at least twenty-five members of the Falkland Islands Defence Force - islanders, plus a Canadian resident and the governor's own chauffeur, who simply offered their services. Against them came an Argentine task force built around submarine-landed frogmen, amphibious commandos, and twenty LVTP-7 armoured carriers. The defenders knew they could not win. They intended to make the seizure of British territory cost something, and to be seen resisting when it happened.

Operation Rosario began in darkness. The submarine ARA Santa Fe landed Buzos Tacticos commandos near Cape Pembroke, who took the airfield and lighthouse without a fight. Then the main force came ashore at Yorke Bay, and the armoured column rolled toward Stanley. Near the Ionospheric Research Station, at exactly 7:15 in the morning, a section of Royal Marines under Lieutenant Bill Trollope opened up with anti-tank rockets and machine guns. The first carrier took a direct hit and stopped dead. For a few minutes a dozen Marines held up an armoured advance, then leap-frogged back through the gardens of the town as the remaining vehicles deployed their troops. They fought from street corner to street corner, withdrawing toward Government House under heavy but mostly inaccurate fire. Years later, after examining the evidence, a British armour expert concluded no Argentine carrier was actually destroyed that morning - though one clearly lost a track to a rocket.

The real fight closed in around the governor's residence. Lieutenant-Commander Pedro Giachino, a volunteer for the mission, led just sixteen men against a building that was - unknown to him - the main Royal Marine strongpoint, defended by more than twice his number. His squads exchanged fire on the lawns while Giachino himself rushed what he thought was the rear entrance. He was cut down instantly in the doorway. Badly wounded, he refused to release the grenade in his hand, and the Marines could not reach him to give aid; after the surrender he was carried to Stanley Hospital but died of blood loss. He was the first Argentine officer killed in the war that his own assault had begun. The Marines' snipers, Corporals Gill and Pares, worked the hillside methodically. Inside, a British war correspondent felt a sniper's round part his hair as it came through a bedroom window. The defenders believed they faced a full company; in truth a dozen commandos were circling them in the dark, shifting positions to seem like many more.

By half past eight, Governor Hunt knew the end had come. Major Norman warned him the defence would be determined but short-lived, and Hunt opened talks under a white flag. "With a heavy heart," he later wrote, "I turned to Mike and told him to give the order to lay down arms. I could not bring myself to use the word 'Surrender.'" The Argentine commander, Admiral Carlos Busser, praised the Marines for fighting with honour and let them keep it. Even in defeat there was care: Major Noott applied a tourniquet and morphine to wounded Argentine soldiers, and one of them, Lieutenant Garcia Quiroga, later said it saved his life. In a final act of defiance, Hunt put on his ceremonial uniform - ostrich plumes and sword - for the drive to the airport and the flight into exile. "We feel as though we are deserting everyone," his wife told a journalist, "but what can we do?" The next day the United Nations demanded Argentina withdraw. Britain was already assembling a task force. The war for the islands had begun.