Treaty of York (1464)

As practical support from Louis XI of France was unlikely Scotland was forced to abandon its alliance with the House of Lancaster and treat with the Yorkist Edward IV of England.

Previously, the Lancastrian Henry VI of England, his wife Margaret of Anjou and son Prince Edward had found refuge in Scotland after the battle of Towton in 1461.

In June 1480, Edward IV gave orders for a large army with artillery to be mustered in the East Riding of Yorkshire from the northern counties, to be led by Richard, Duke of Gloucester.

In March 1481 Edward commissioned cannon and gunners for a naval expedition against Scotland of eleven warships under the command of Richard Simmons, Master of the Grace Dieu, and in June renewed his league with the John, Lord of the Isles and Donald Gorve (Gorm).

On 11 June 1482, at Fotheringhay Castle, the younger brother of James III, Alexander Stewart, Duke of Albany, declared himself King of Scotland, and promised by treaty to deliver Berwick and other places to Edward and break the Auld Alliance with France.