John Wenlock , 1st Baron Wenlock John Wenlock , 1st Baron Wenlock KG ( died 1471 ) was an English soldier , courtier and politician . He fought on the sides of both the Yorkists and the Lancastrians in the Wars of the Roses . One historian has gone so far as to call him " Prince of Turncoats . " Early life . He was the son of William Wynell de Wenlock , commonly called William Wenlock , knight of the shire for Bedfordshire in 1404 , by his wife Margaret Breton , an heiress of Houghton Conquest in Bedfordshire . John Wenlock took part in the invasion of France under Henry V of England , and on 16 August 1421 he received a grant of lands in the bailiwick of Gisors in Normandy , and shortly after , in April 1422 , is styled constable of Vernon . In 1433 he was returned to parliament for Bedfordshire , and again in 1436 , 1447 , 1449 , and 1455 . He was elected Speaker of the House in the 1455 Parliament . He was escheator for Buckinghamshire and Bedfordshire in 1438 – 9 , and he early entered the service of Margaret of Anjou , being first usher of the chamber , and about 1450 to her . In this capacity he laid the first stone of Queens ' College , Cambridge , on 15 April 1448 . He served also in 1444 as High Sheriff of Bedfordshire and Buckinghamshire . Wenlock ' s seat was at Luton , his property there , Someries castle , coming through inheritance . In 1462 he acquired Hertfordshire property forfeited by the former Chief Justice , Sir John Fortescue . His service to the Crown is also reflected in his employment as a member of some 18 embassies in the 1440s and 1450s . He was knighted in 1449 . It appears to have been at one such embassy that he came into contact with the Duke of York and the Earl of Warwick , and he became a supporter of the latter . In the Wars of the Roses . During the Wars of the Roses , Wenlock initially fought for the House of Lancaster in the First Battle of St Albans on 22 May 1455 , but his relationship with Warwick led him to subsequently change sides , and it was as a Yorkist that he served as Speaker of the House of Commons later that year in the parliament of 1455 . By the Battle of Blore Heath in 1459 Wenlock fought for the House of York . He also fought under the Yorkist banner in the Battle of Mortimer ' s Cross , the Second Battle of St Albans and the Battle of Towton , all in what is referred to as the first phase of the War of the Roses . Having successfully besieged the Tower of London for Edward of York , he was part of the latter ' s triumphal entry into London in 1461 and was elected a knight of the Garter a few days after . Later in the year he received appointment as Chief Butler of England and was made Baron Wenlock . In 1464 he helped Lord Hastings capture Dunstanburgh Castle . He continued to undertake diplomatic missions for Edward IV , and had command of Calais for him ( possibly as deputy of Warwick ) . When Warwick defected to the Lancastrian camp , Wenlock did not immediately follow him back , however his sympathies clearly remained with his friend , and by 1471 he too had switched sides , accompanying Margaret of Anjou back to England . Death . At the Battle of Tewkesbury on 4 May 1471 , he commanded the middle of the Lancastrian line . However , the Lancastrians suffered a crushing defeat , and Wenlock died on the battlefield . He was allegedly killed by his own commander , the Duke of Somerset , who blamed Wenlock ' s indecisiveness for the defeat . The Duke of Somerset had led the right flank of the Lancastrian line forward , and expected Wenlock to support him , but Wenlock held back ( some suggest deliberately ) and the Duke ' s men were slaughtered . After the Duke ' s flank retreated he summoned Wenlock and supposedly killed him with a single blow of his mace to the head . Family . Wenlock died without issue , and his title died with him . It has been argued that Wenlock did not actually die on the field at Tewkesbury , but together with his second wife , Agnes ( widow of Sir John Fray ) , perpetuated a hoax by burying another body , and he then lived on for several more years . However , Agnes remarried ( for the third time ) at some point between September 1473 and October 1474 ( to Sir John Say ) , which casts doubt on the assertion that Wenlock survived six or seven years after Tewkesbury .