John McGuire was a resident of Chowan County, North Carolina. In 1778 he married Sarah Bunch, making Ishmael Bunch his brother-in-law and Josiah Small his step father-in-law. In 1782 McGuire testified before the court regarding two separate cases involving Sal, an enslaved African American man. In one case, Elizabeth Jones took Sal from McGuire's step father-in-law, and in another case his brother-in-law then took Sal from Jones. McGuire died in Chowan in about 1807.