Arthur Plantagenet, 1st Viscount Lisle, KG (died March 3, 1542) was an illegitimate son of King Edward IV of England.

He was born in France at Calais, between 1461 and 1475, and died at the Tower of London, where he is buried. The identity of his mother is uncertain. She may have been one of King Edward's mistresses, Elizabeth Lucy or Elizabeth Wayte, in all probability separate women. His godfather was Thomas Fitzalan, 16th Earl of Arundel .

Arthur Plantagenet was first married on November 12, 1511, to Elizabeth Dudley, Baroness Lisle, daughter of Edward Grey, Viscount Lisle , by his wife, Elizabeth Talbot, daughter of John Talbot, Viscount Lisle. Elizabeth was the widow of Edmund Dudley, treasurer to Henry VII, who had been executed in 1509 by Henry VIII. Elizabeth de Lisle, a descendant of Richard Neville, 16th Earl of Warwick, was the mother of John Dudley, 1st Duke of Northumberland. By Elizabeth, Arthur Plantagenet had three daughters, Bridget, Elizabeth and Frances Plantagenet.

Arthur married secondly, in 1529, Honor Grenville, (1493-1566) the widow of Sir John Basset, and daughter of Sir Thomas Grenville, a daughter of Sir Thomas Grenville by his first wife, Isabella Gilbert.

Overshadowed by a host of legitimate male relatives, Arthur only achieved prominence under the Tudor dynasty. In 1514 he was captain of the Vice-Admiral's ship "Trinity Sovereign ", rising to become Vice-Admiral of England. He attended his nephew, King Henry VIII, at the Field of Cloth of Gold in 1520. Arthur's peerage was a new title, created for him on the 25th of April in 1523 by Henry VIII. He was also to be selected Sheriff of Hampshire, Privy Councilor, Governor of Calais, and Lord Warden of the Cinque Ports. 'Lisle was named as deputy of Calais after the death of John Bouchier , Lord Berners on March 16, 1533. Lisle was sworn into office on the 10th of June'.

In the 'Lisle Letters' principally of a private nature, dating from Lisle's appointment in Calais and written by Arthur Plantagenet it is revealled he was styled "cousin" by Margaret Pole, Countess of Salisbury. The Lisle Letters were collated in six volumes of about 3000 papers as a body of evidence in the trial that followed Lisle's accusation of treason. They culminate in his confinement in the Tower of London.

"Their main correspondent was John Husee, Lisle's agent and secretary, based in London, whose letters are full of valuable political detail".

He was imprisoned in the Tower on suspicion of treason on May 19, 1540, for charges of plotting to betray Calais (then an English domain) to the French. When the verdict came in acquitting him, he is reported to have died of an heart attack. His widow, Honor, was buried at Logan, Cornwall 30 Apr 1566.