Royal Ancestry by Douglas Richardson Vol. II page 599
Richard (FitzAlan-606) or De (Arundel) and other's ...
RICHARD (FITZ ALAN (or DE ARUNDEL)
[Footnote 25] Earl Richard Fitz Alan (FitzAlan606) above, his father and grandfather all employed the surname Fitz Alan . In the 1270's, Earl Richard's father was styled John "Fitz Alan de Arundel" in several records [see C.P.R. 1272-1281 (1901): 11, 96, 161, 331]. ...
Following Earl Richard's death in 1302, the family dropped the surname Fitz Alan in favor of de Arundel (or simply Arundel). The last known use of the name Fitz Alan by any member of this family dates c.1312-3, when Earl Richard's son, Edmund, brought a writ as "Edmund Fitz Alan" [see Year Books of Edward III 12 (Rolls Ser. 31b) (1905): 518-521]. Thereafter, all further references to this family employ the surname Arundel to the complete exclusion of the surname Fitz Alan.
Specifically, Earl Richard's son Edmund (died 1326), both of his brothers, two of his sons and all four of his grandsons all employed the Arundel surname. Edmund's sister Alice is likewise styled "de Arundel" in an ancient Segrave Family ped. VCH Surrey 1 (1902): 348, footnote 1 observes that Richard's son and heir, Edmund, is "commonly called Fitz Alan but the real designation of the family was then de Arundel." Nicholas, a well known antiquarian, states: "This family presents a singular instance of adopting the name of their title as the surname of the fmaily, for after the marriage of John Fitz-Alan, Lord of Clun, with Isabel, the sister and co-heir of Hugh D'Albini, Earl of Arundel, all the descendants called themselves Arundel instead of Fitz-Alan" [see Nicolas Testamenta Vetusta 1 (1826): 105]. "J.G.N." in Gentleman's magazine 103 Oxfordshire, etc., .....
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