William Tailboys, de jure 7th Baron Kyme (c.1416 – 26 May 1464) was a wealthy Lincolnshire squire and adherent of the Lancastrian cause during the Wars of the Roses.
William gained a reputation as a troublemaker, continually disputing with his neighbours, particularly Lord Cromwell, the ex-Treasurer.
However his unruly character led to his temporary imprisonment in the Marshalsea, London in 1448 for a series of murders and trespasses.
He also fought at the Battle of Towton in 1461, escaped and was declared a rebel and had his property confiscated by King Edward IV.
He was later discovered hiding in a coal pit near Newcastle with some 3000 marks (2000 pounds) of Lancastrian funds which had been intended as pay for the army.