William de la Pole, 4th Earl and 1st Duke of Suffolk (1396 – May 2, 1450), was an important English soldier and commander in the Hundred Years' War, and later Lord Chamberlain of England. He also appears prominently in Shakespeare's Henry VI, part 1 and Henry VI, part 2.

He was seriously wounded during the siege of Harfleur (1415), where his father, the 2nd Earl, was killed. Later that year his older brother was killed at the Battle of Agincourt, and he succeeded as 4th Earl. At the siege of Orléans (1429) he became co-commander of the English forces after the death of the Earl of Salisbury, but was captured by the French a few days later. He remained a prisoner for three years, and was ransomed in 1431.

After his return to England, he became a courtier and close ally of Cardinal Beaufort. His most notable accomplishment in this period was negotiating the marriage of King Henry VI with Margaret of Anjou (1444). This earned him elevation to Marquess.

With the deaths in 1447 of Humphrey, Duke of Gloucester and Cardinal Beaufort, Suffolk became the principal power behind the throne of the weak and compliant Henry VI. In short order he was appointed Chamberlain, Admiral of England, and to several other important offices. The next year he was raised to the rank of duke.

The following three years saw the near-complete loss of the English possessions in northern France, and Suffolk could not avoid taking the fall for the failure. On January 28, 1450 he was arrested and imprisoned in the Tower of London. He was banished for five years, but on his journey to France his ship was intercepted, and he was executed. The person or persons behind his death remain a mystery.

Interesting footnote: He seduced a nun and got her pregnant.

"The nighte before that he was yolden (yielded himself up in surrender to the Franco-Scottish forces of Joan of Arc on 12 June 1429) he laye in bed with a Nonne whom he toke oute of holy profession and defouled, whose name was Malyne de Cay, by whom he gate a daughter, nowe married to Stonard of Oxonfordshire". [Hist. MSS Com.3rd Rep.,pp.279-280. Source: Leo van de Pas]