Editors. "James IV of Scotland invades Northumberland in support of Perkin Warbeck". The Literary Encyclopedia. First published 01 November 2010
[http://www.litencyc.com/php/stopics.php?rec=true&UID=13956, accessed 20 May 2013.]
James IV of Scotland invaded Northumberland in support of Perkin Warbeck's claim to the English throne. However, he received less support than expected, and soon retreated. As a result, James IV signed the Treaty of Ayton with Henry VII and expelled Warbeck from his court.