The son of Colonel Henry Hyrne and his wife Susannah Bellinger, Edmund Hyrne served as a captain and then a major in the First South Carolina Contenental Regiment under Christopher Gadsden. In 1778 he was appointed to serve as deputy adjutant general of the Southern Department. In 1781 he arranged for an exchange of American prisoners captured by the British and was officially thanked by Congress for his efforts during the battle of Eutaw Springs, where he was wounded. After the war, Hyrne served in the South CArolina General Assembly which met at Jacksonborough, and lived on his plantation called Ormsby, in St. Bartholomew's Parish, South Carolina.