Alexander Stewart, 1st Duke of Albany (c. 1454 - 7 August 1485) was the second son of King James II of Scotland, and his wife Mary, daughter of Arnold, Duke of Gelderland.

Created Duke of Albany before Isle of Man, and was afterwards captured by an English ship while journeying to Gelderland in 1468. He was soon released, and as he grew to manhood began to take part in the government and defence of Scotland, being appointed in quick succession high admiral, warden of the marches, governor of Berwick and lieutenant of the kingdom. Soon, however, he quarrelled with his brother, King James III. Some of his actions on the marches aroused suspicion, and in 1479 he was seized and imprisoned in Edinburgh Castle; but he soon made his escape, and reaching Paris in September 1479 was welcomed by King Louis XI. Louis, however, would not assist him to attack his brother the king, and crossing to England he made a treaty with King Edward IV at Fotheringhay in June 1482.

Like Edward Balliol, he promised to hold Scotland under English suzerainty in return for Edward's assistance, and with Richard, Duke of Gloucester, afterwards King Richard III, he marched at the head of the English forces to Edinburgh. Meanwhile his supporters in Scotland had seized James, and professed their readiness to recognize Albany, declaring at the same time their distrust of Gloucester. A compromise, however, was arranged, and the restoration of his lands and offices was promised to Albany, who in turn agreed to be faithful to James; but about the same time the duke with remarkable duplicity had'sworn he would keep the treaty with Edward. Again he was appointed lieutenant of the kingdom, a truce was made with the English, and James, released from custody, restored his brother and created him earl of Mar and Garioch.

The fraternal peace was soon disturbed. Failing to obtain possession of the king's person, Albany renewed negotiations with Edward, and in February 1483 made a new treaty at Westminster on the lines of that of Fotheringhay. A fresh reconciliation followed between the brothers, but in July 1483, during Albany's absence in England, he was sentenced to death for treason. After making a raid on Lochmaben he went to France, where in 1485 he was accidentally killed. Albany's first wife was Catherine, daughter of William Sinclair, 3rd Earl of Orkney, who bore him three sons and a daughter. This marriage was dissolved in 1478, and as its issue was regarded as illegitimate the title of duke of Albany descended to John (see below), his only son by his second wife, Anne de la Tour d'Auvergne, daughter of Bertrand II, count of Auvergne and of Bouillon, whom he married in 1480.