Massacre of Glencoe, (February 13, 1692), in Scottish history, the treacherous slaughter of the MacDonalds of Glencoe by soldiers under Archibald Campbell, 10th earl of Argyll. Many Scottish clans had remained loyal to King James II after he was replaced on the British throne by William III in 1689. In August 1691 the government offered an indemnity to all chiefs who should take an oath of allegiance before January. 1, 1692. "Letters of fire and sword," authorizing savage attacks upon recalcitrants, were drawn up in anticipation of widespread refusals; the chiefs, however, took the oath. Alexander MacDonald of Glencoe postponed his submission until December. 31, 1691, and was then unable to take his oath until January 6 because there was no magistrate at Fort William to receive it. An order for military punishment was thereupon issued under William III's signature. More than 100 soldiers from Fort William who had been quartered amicably upon the MacDonalds for more than a week suddenly attacked them; many of the clan escaped, but the chief, 33 men, 2 women, and 2 children were killed. John Campbell, earl of Breadalbane, a neighbour and enemy of the MacDonalds, was widely suspected of planning the attack but was not its main instigator; his imprisonment in 1695 was for earlier involvement with the Jacobites.