Main Blackett Tree

Second son of Sir William Tempest. According to The Northern Genealogist 1895 he was an illegitimate son of Sir William. The Pedigree and History of the Washington Family by Albert Welles (1879), however, shows him as the 2nd son of Sir Rowland Tempest and Eleanor Washington. Mentioned in the entail of the family estates, but only after both Sir William's daughters and their heirs.
Burke's General Armory (probably following Surtees) maintains that he acquired Holmeside by gift of Sir Robert Umfraville, but The Northern Genealogist 1895 states that this is incorrect and he acquired Holmeside through his wife's inheritance and through purchase. The History of Parliament states that "A cadet branch of the Tempests of Bracewell had been settled at Holmside since Sir Robert Umfreville, himself one of the cadet line of a great house, chose as his heir the Tempest husband of one of his four great-nieces." This appears to refer to Isabella Elmeden and thus supports Burke's General Armory.
Burke's Peerage, 2003 shows him as illegitimate.
By charter dated 12 May 1440 his father William assigns to him all his lands and tenements in Thornton-le-Street and Northallerton. The charter was inspected by William's eldest [and legitimate] son and heir William Tempest, who confirmed the gift to "Rolando Tempest fratre meo" by deed dated 20 May 1443 and further gave to Roland all the lands which belonged to Richard Tempest "aui mei" or to [his] father in the vill or territories of Thirsk and Otrington. (Source: The Northern Genealogist.)

Possibly in May 1440, when Sir William Tempest gave the estate of Thornton-le-Street to Roland Tempest.