Carrickfergus was built by John de Courcy in 1177 as his headquarters, after he conquered eastern Ulster in 1177 and ruled as a petty king until 1204, when he was ousted by another Norman adventurer, Hugh de Lacy. Initially de Courcy built the inner ward, a small bailey at the end of the promontory with a high polygonal curtain wall and east gate. It had a number of buildings, including the great hall. From its strategic position on a rocky promontory, originally almost surrounded by sea, the castle commanded Carrickfergus Bay (later known as Belfast Lough), and the land approaches into the walled town that developed beneath its shadows.