William Pick says he is owned by Sir Thomas Oglethorpe of Scotland. However, he is almost certainly owned by Sir Theophilus Oglethorpe who was frequently referred to as Sir Th. Oglethorpe, resulting in Pick's erroneous statement. Sir Theophilus Oglethorpe (died 1702) was the brother of Sutton Oglethorpe, Studmaster (1674-1688) to Charles II and James II, Sir Theophilus later holding the same position. The Oglethorpe Arabian (OA) was probably owned by each of them at some time. The GSB states that "This may be the horse described as Mr. Oglethorpe's son of the Yellow Turk". However, its entry on Darcy's Yellow Turk (DYT) doesn't mention OA among his progeny.
Lord Rockingham's pedigree collection says "Makeless was got by General Oglethorpe's Arabian; dam by Lord D'Arcy's Yellow Turk; out of a natural Barb Mare..", making Makeless inbred 2x2 to DYT, which would make it seem less likely OA was sired by DYT
OA sires Makeless, sire of many significant broodmares, especially in Families 2,4, 25 and 33; and the dam of Bay Bolton, 7 times Champion Sire