On 10 May 1607, the Scottish king James VI also King James I of England granted the native Irish chief, Ruairí Óg MacQuillan the Ballymena Estate. The estate passed through several owners, eventually passing into the possession of William Adair, a Scottish laird from Kinhilt in southwestern Scotland. The estate was temporarily renamed "Kinhilstown" after Adair's lands in Scotland. The original castle of Ballymena was built in the early 17th century, situated to take advantage of an ancient ford at the River Braid. In 1626 Charles I confirmed the grant of the Ballymena Estate to William Adair, giving him the right to hold a market at Ballymena on every Saturday. He hired local Irish as workers on the estate; they served as tenant farmers for much of the next two centuries and more.