The castle was built in 1228 by the Anglo-Norman House of Burke following their defeat of the O’Connors, the Royal House of Connacht, who are still extant in the person of the O’Conor Don. The de Burgos would build several such castles throughout the province, including one on the mouth of the River Corrib around which was to grow the City of Galway, but Ashford would remain their principal stronghold in the vastness of a wild and untamed province. The principal legacy of the native O’Connors is to be seen at the gates of the estate in the form of the Romanesque Augustinian Abbey of Cong. It is in this abbey that Ireland’s last High King Ruaidrí Ua Conchobair died and from which came the greatest relic of his Court, the Cross of Cong, created to hold a piece of the True Cross and now in the National Museum of Ireland.
After more than three and a half centuries under the de Burgos, whose surname became Burke or Bourke, Ashford passed into the hands of a new master, following a fierce battle between the forces of the de Burgo’s and those of the English official Sir Richard Bingham, Lord President of Connaught, when a truce was agreed. In 1589, the castle fell to Bingham, who added a fortified enclave within its precincts. In 1715, the estate of Ashford was established by the Browne Family (Baron Oranmore), and a lodge in the style of a 17th-century French chateau was added to the medieval splendour of the castle.