Cirion was the High-captain of Gondor's fleet during the reign of his father Boromir. He became the twelfth Ruling Steward in T.A. 2489 and ruled Gondor until his death in T.A. 2567. Cirion presided over a beleaguered Kingdom, one assailed by Corsairs in the South and the Balchoth in the North; and although he was an able and exceedingly brave Captain, his armies were overmatched. He managed to stop the Corsairs, but the Easterling confederation of the Balchoth swept across the Anduin and into northern Gondor in T.A. 2510. Cirion rode north to meet the invaders but found his army hard-pressed. Fortunately, Eorl of the Éothéod came to Cirion's rescue at the Battle of the Field of Celebrant, where the Steward and his Northman allies defeated the Balchoth and ended the invasion of Calenardhon (Gondor's north- em province). Cirion then granted the Northmen of the Eotheod all of Calenardhon, which became Rohan. In return, Eorl swore his famous oath of alliance to the South Kingdom.