The Nicholas family goes back to 1280 AD when Baron Gilbert de la Roche granted the manor of Roundway on the road around Devizes in Wiltshire to William Nicholas.
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Dr. George Nicholas was of the junior Alcannings line that fought with Cromwell in the English Civil War and suffered the wrath Edward Nicholas, secretary of State under Charles I and II, who was of another junior line seated in Winterbourne Earls.
The plantation and slave were doubtlessly inherited from Robert Carter by Elizabeth and seems to have passes to her son John Nicholas. The slaves often took the family names of their owners. As Old Jack seems to have done.