Micajah Thomas was born in Virginia in February 1726. A resident of Edgecombe County, North Carolina, Thomas was a prominent planter and enslaver in the area. In 1765 he served on the local freeholders court when it heard a case involving Jamey, an enslaved man charged with theft. Thomas later represented Edgecombe in the North Carolina Colonial Assembly in 1769 before he died in about December of that year.