Andrew Stewart (c. 1426 – 1488) was Lord Chancellor of Scotland from 1460 to 1482 and one of the leading servants of King James III of Scotland.
In 1460 he was appointed Chancellor by King James II of Scotland who died later that year. Avandale retained the officer of Chancellor, and may have briefly served as regent, during the minority of King James III of Scotland. He then served as governor of Stirling Castle and as an ambassador and diplomat, taking a leading role in the negotiations which led to the marriage of James and Margaret of Denmark in 1469. In 1471 he was granted the rents of the Earldom of Lennox for life.
During the crisis of 1482, when James III declared war on England for protecting his brother Alexander Stewart, Duke of Albany, who had rebelled and was given sanctuary by the Duke of Gloucester, who later became King Richard III. When Albany and his English allies invaded Scotland, Lord Avandale was one of the faction who refused to fight and then proceeded to arrest the King. Albany then proclaimed himself King Alexander IV of Scotland and immediately began to alienate the nobles by his harsh policies, especially the powerful George Gordon, 2nd Earl of Huntly.
On Alexander's orders, Lord Avandale was then stripped of the Chancellorship because he had captured Albany's castle of Dumbarton for the King in 1479. He was replaced as Lord Chancellor by John Laing, the Bishop of Glasgow. Because of Alexander's treatment of the nobles, James III had been able to gain back most of their support and in 1483 with help from the Earl of Huntly, James was able to call a Parliament that condemned Albany as a traitor and forced him into exile for a second and final time. Avandale had been present at the Parliament and the following year he was one of the ambassadors sent to Louis XI of France. After this he appears to have largely withdrawn from public business. He died in 1488 and was succeeded by his brother Walter's son Alexander. Alexander died c. 1500 and the title Lord Avandale passed to another nephew, Andrew Stewart, 2nd Lord Avandale.
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