The Lands of Garleton and the original house were a property of the Lindsay family, but were eventually acquired by the Lords Seton. Garleton as an expanded castle was begun by Sir John Seton, 3rd son of George 7th Lord Seton, the celebrated Knight of the Order of Malta, Master of the Kings Bedchamber and Master of the Household of the King of Spain, and later, King James VI and I's Treasurer, Lord of Session, Master of the Kings Household for life and Master of the Kings Horse. He was Baron of Barnes and acquired various lands around Amisfield and Haddington and began developing the lands and estates quite vigorously but died relatively early in life. He was slated to be elevated higher in the peerage and his death was of great loss to the King. The estate of Garleton eventually passed to the son of George Seton, 3rd Earl of Winton and the eldest son of his second marriage. Of these 2nd Seton's of Garleton, they were briefly recognized as the heirs of the Earldom of Winton after George, 5th Earl died in exile Rome 1749.