William's father had died in the September of 1415 at the Siege of Harfleur and his older brother Michael had died at the Battle of Agincourt thus William became the 4th Earl of Suffolk. He was created Earl of Pembroke in 1447 and Duke of Suffolk in 1448. He had married Alice Chaucer, the granddaughter of poet Geoffrey Chaucer in 1430 with whom he had one son, John.
William de la Pole was a one time favourite of Henry VI he was an English commander who sadly is remembered and blamed for the loss of French territories of Maine and Anjou, these lands formed part of the marriage contract of Henry VI to Margaret of Anjou that Pole had arranged.
Pole was blamed for much, a scapegoat, who was exiled and murdered on route to Calais.