Research Notes:
The Oxford DNB states, [1]
[The de Beauchamp family (per. c.1080-c.1265)] held a modest barony of about forty-five knights' fees, predominantly in Bedfordshire, with some land in Buckinghamshire, Hertfordshire, Cambridgeshire, Essex, and Huntingdonshire. … No connection has been found to the Beauchamps of Worcester. The family was first represented by Hugh de Beauchamp (fl. 1080-c.1118), presumably of Norman origin, who acquired his lands and position through marriage to Matilda, apparently the daughter and heir of Ralf Tallebosc, post-conquest castellan of Bedford and sheriff of Bedfordshire, and Azelina, who held lands in Bedfordshire and Cambridgeshire in her own right. … Hugh seems to have had at least two sons, Simon and Robert. Simon [i] de Beauchamp (d. 1136/7), who witnessed King Stephen's charter of liberties as royal steward in 1136, was probably the eldest son and heir to the barony. His daughter married Hugh Poer, who was granted the honour and castle of Bedford and created earl by King Stephen, to the anger of Robert's sons, who believed they were being deprived of their rightful inheritance.
Chambers and Fowler provide a history of the Beauchamp family, starting with Hugh de Beauchamp. [2]
[1] Kathryn Faulkner, "Beauchamp, de, family (per. c.1080–c.1265)," Oxford Dictionary of National Biography (Oxford University Press, 2004, online edition), [Oxford_Dictionary_National_Biography], [OxfordDNB(UM)].
[2] C. Gore Chambers and G. Herbert Fowler, "The Beauchamps, Barons of Bedford," The Publications of the Bedfordshire Historical Record Society, vol. 1 (1913), 1-26 at 1-3, [InternetArchive].