David Johnston, Sr. was born in 1753 to Robert and Mary Johnston. He was the grandson of David and Mary Boyd Johnston and the husband of Sarah Neel. The Johnstons descend from Clan Johnston of Annandale Scotland. Clan Johnston was among the fiercest of the borderers. The Clan was warlike, proud, and extremely brave. David's great, grandfather, Thomas Boyd, served with the Army of William of Orange. He fought in The Battle of The Boyne, in Northern Ireland. The Boyds and Johnstons were Presbyterians. David Johnston was a Revolutionary War soldier
David and his wife, Sarah, resided on their share of the Neel tract of land about four hundred yards above the Buster Boyd Bridge at the present site of Lake Wylie, South Carolina. David was a farmer and was a breeder of and raced thoroughbred horses. He met his death at the hands of one of these creatures, bring thrown against a tree and suffered a broken neck. He died October 15, 1794 at the age of forty one years. He is buried in Bethel Church Cemetery.
David and Sarah had four daughters, Sarah, Mary, Jean, and Elizabeth, and one son, David, Jr.