William Fitzalan, 16th Earl of Arundel (23 November, 1417 - 1487).

He was a son of John Fitzalan, 13th Earl of Arundel and Eleanor Berkeley. His mother was a daughter of John Berkeley and Elizabeth Betteshorne, granddaughter of Thomas de Berkeley, 3rd Baron Berkeley and his second wife Catherine Clivedon.

His elder brother John Fitzalan, 14th Earl of Arundel died on June 12, 1435. The title passed to his nephew Humphrey Fitzalan, 15th Earl of Arundel who was still a six-year-old with no descedants. William thus became his Heir presumptive. He succeeded him on 24 April, 1438.

The new Earl married Joan Neville. Joan was a daughter of Richard Neville, 5th Earl of Salisbury and Alice Montagu, Countess of Salisbury. Alice was a daughter of Thomas Montacute, 4th Earl of Salisbury and Eleanor Holland. Eleanor was a daughter of Thomas Holland, 2nd Earl of Kent and Alice Fitzalan. Alice was a daughter of Richard Fitzalan, 10th Earl of Arundel and Eleanor of Lancaster.

William and Joan had five children:

• Thomas Fitzalan, 17th Earl of Arundel (1450 - 1524).
• William Fitzalan. An alleged maternal ancestor of Thomas Stucley.
• George Fitzalan.
• John Fitzalan.
• Mary Fitzalan.
• Thomas Fitzalan.

William fought in the Second Battle of St Albans (22 February, 1461) as a supporter of the House of York. The Yorkists were commanded by his brotherin-law Richard Neville, 16th Earl of Warwick. They succeeded in capturing Henry VI of England.

Edward IV of England named him a Knight of the Garter in 1471. Probably in honor of his support during the Wars of the Roses.