Cannon and other artillery were in use during the Wars of the Roses - there are traces at the Battle of Towton and the Battle of Bosworth.
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Bamburgh Castle, in 1464, during the Wars of the Roses, became the first castle in England to be defeated by artillery at the end of a nine-month siege by Richard Neville, 16th Earl of Warwick.
James II of Scotland was killed by the explosion of a cannon, Mons Meg, in 1460.