The lands of the Castle of Ballalekan, or Moneylagan near Longford town, were acquired by Sir John Seton 2nd of Barnes, from Sir Robert Gordon of Lochinvar in 1624. He received a charter in 1628 noted in the Calendar of the patent and close rolls of chancery in Ireland during the reign of King Charles I, for the Estate of MoneyLagan, or Balleleghan (Babington), Longford, Ireland.

"Grant to Sir John Seton, his heirs and assigns, for ever, as an undertaker, of 2,000 acres arable and pasture, and 1,104 acres bog and wood, in the barony and county of Longford ; a portion of 'which is to be held of the King in capite by knight's service, and the residue of the Castle of Dublin, in free and common soccage. The lands are erected into a manor, to be called the manor of Monelagan, otherwise Balleleghan, with power to create tenures, and hold a court leet, court baron, a weekly market on every Thursday at the town of Killeene, and two fairs at Monelagan, alias Balleleghan, one on the 20th April, and the other on the 20th October, with such covenants, conditions, and provisoes as are contained in the patents of undertakers of the territory of Ely O'Carroll.—Dublin. August 8,4°."