Jacob Oldacre was born in Buckland, Gloucestershire, England in 1688 and was married to Elizabeth Clifford in Oddington, Gloucestershire, England on 21 June 1721. one daughter is known: Isabell (born 1728).

A Jacobus Oldacre was baptised in Stanton, Gloucestershire, England on 08 September 1679. His parents were Guilelmus and Elizabethae Oldacre.
Another Jacobus Oldacre was baptised in the Church of All Saints in Alrewas, Staffordshire, England on 07 October 1684. His father was Thomas Oldacre.