James I (late July 1394 – 21 February 1437) was King of Scots from 1406 until his assassination in 1437. The youngest of three sons, he was born in Dunfermline Abbey to King Robert III and Annabella Drummond. His eldest brother David, Duke of Rothesay, died under suspicious circumstances while detained by his uncle, Robert, Duke of Albany. James's other brother, Robert, died young. Concerns for James's safety deepened in the winter of 1405–1406 prompting plans to send him to France. In February 1406, James took refuge in the castle of the Bass Rock in the Firth of Forth after his escort was attacked by supporters of Archibald, 4th Earl of Douglas. He remained there until mid-March when he boarded a vessel bound for France. On 22 March, an English vessel captured the ship and delivered James to Henry IV of England. The ailing Robert III died on 4 April and the 11-year-old James, now the uncrowned King of Scotland, would remain in captivity for eighteen years.
James was educated well during his imprisonment in England, where he was often kept in the Tower of London, Windsor Castle, and other English castles. He was generally well-treated and developed respect for English forms of governance. James joined Henry V of England in his military campaigns in France between 1420 and 1421. His cousin, Murdoch Stewart (Albany's son), an English prisoner since 1402, was traded for Henry Percy, 2nd Earl of Northumberland, in 1416. However, Albany refused to negotiate James's release. James married Joan Beaufort, daughter of the Earl of Somerset, in February 1424, shortly before his release in April. His return to Scottish affairs was not altogether popular due to his service to Henry V in France, sometimes against Scottish forces. Noble families faced increased taxes to fund the ransom payments, and to provide family hostages as security. James, who excelled in sports, literature, and music, aimed to impose law and order on his subjects but sometimes he applied such order selectively.