He was the son of John Fitzalan, from whom he inherited a great estate in Shropshire, and Isabella, daughter of William d'Albini, 4th Earl of Arundel. After the death without direct heirs of his mother's brother Hugh d'Albini, 5th Earl of Arundel, he inherited a quarter of the earl's estate, including Arundel.
Arundel vacillated in the conflicts between Henry III and the barons. He fought on the king's side at the Battle of Lewes, where he was taken prisoner.
{| border="2" align="center"
|-
|width="30%" align="center"|Preceded by:
Hugh d'Aubigny
|width="40%" align="center"|Earl of Arundel
|width="30%" align="center"|Followed by:
John Fitzalan
|}