half brother of Mary Stuart, Queen of Scots, who became regent of Scotland after her abdication.

The illegitimate son of King James V and Lady Margaret Douglas, Stewart led the Protestant lords in their conflict with Mary Stuart's mother, Mary of Lorraine, the queen regent. When Mary Stuart assumed control of the government upon the death of her mother in 1560, however, he supported her, despite her Roman Catholicism. In 1562 she made him Earl of Moray and Earl of Mar, but he lost her favour by supporting the Calvinist reformer John Knox and by opposing the queen's marriage (July 1565) to Henry Stewart, Lord Darnley. From August to October 1565, Moray attempted to arouse Edinburgh citizens against Mary's authority. She personally led the force that drove him and his supporters across the border. The outlawed Moray fled to England but was pardoned and allowed to return to Scotland the following year. When Mary abdicated in 1567, Moray was appointed regent for her year-old son, King James VI. He suppressed her final effort to regain power when he routed her forces at Langside on May 13, 1568, and she, in turn, fled to England. A substantial portion of the nobility continued to maintain Mary's right to rule, however, and Moray had difficulty putting into practice his vigorously Protestant and pro-English policies. In January 1570 he was assassinated by James Hamilton of Bothwellhaugh, who favoured Mary, while riding through Linlithgow.