Simnel was born around 1477. His real name is not known—contemporary records call him John, not Lambert, and even his surname is suspect. Different sources have different claims of his parentage, from a baker and tradesman to organ builder. Most definitely, he was of humble origin. At the age of about ten, he was taken as a pupil by an Oxford-trained priest named Richard Simon who apparently decided to become a kingmaker. He tutored the boy in courtly manners and contemporaries described the boy as handsome. He was taught the necessary etiquette and was well educated by Simon.
Pretender
Simon noticed a striking resemblance between Lambert and the sons of Edward IV, so he initially intended to present Simnel as Richard, Duke of York, son of King Edward IV, the younger of the vanished Princes in the Tower. However, when he heard rumours that the Earl of Warwick had died during his imprisonment in the Tower of London, he changed his mind. The real Warwick was a boy of about the same age, having been born in 1475, and had a claim to the throne as the son of George Plantagenet, 1st Duke of Clarence, King Edward IV's executed brother. According to James A. Williamson, Simnel was merely a figurehead for a rebellion that was already being planned by the Yorkists:
He was merely a commonplace tool to be used for important ends, and the attempt to overthrow Henry VII would have taken place had Simnel never existed. The Yorkist leaders were determined on a serious push, rising of their party in England supported by as great a force as possible from overseas.
Simon spread a rumour that Warwick had actually escaped from the Tower and was under his guardianship. He gained some support from Yorkists. He took Simnel to Ireland where there was still support for the Yorkist cause, and presented him to the head of the Irish government, the Earl of Kildare. Kildare was willing to support the story and invade England to overthrow King Henry. Simnel was paraded through the streets, carried on the shoulders of "the tallest man of the time", an individual called D'Arcy of Platten.
Simnel's army—mainly Flemish and Irish troops—landed on Piel Island in the Furness area of Lancashire on 5 June 1487 and were joined by some English supporters. However, most local nobles, with the exception of Sir Thomas Broughton, did not join them. They clashed with the King's army on 16 June at the Battle of Stoke Field in Nottinghamshire, and were defeated. Lincoln and Thomas FitzGerald were killed. Lovell went missing; there were rumours that he had escaped to Scotland with Sir Thomas Broughton and hidden to avoid retribution. Simons avoided execution due to his priestly status, but was imprisoned for life. Kildare, who had remained in Ireland, was pardoned.
Later life
King Henry pardoned young Simnel and put him to work in the royal kitchen as a spit-turner. When he grew older, he became a falconer. Almost no information about his later life is known. He died some time between 1525 and 1535. He seems to have married, as he is probably the father of Richard Simnel, a canon of St Osyth's Priory in Essex during the reign of Henry VIII.
Cultural depictions
In the 1972 BBC serial The Shadow of the Tower, Simnel was portrayed by Gary Warren. In 1996, Blyth Power's album Out From Under the King included a song, Lambert Simnel. In 2006 Steeleye Span's album Bloody Men included a song, The Story of the Scullion King, about Simnel. In the 2017 Starz miniseries The White Princess, Simnel is portrayed by Max True. The 2017 children's book The Player King, by Avi, offers a fictionalized first-person account of the key period of Simnel's life.