England–Wales border after Harold's death at the Battle of Hastings, Wales was again divided without a leader to resist the Normans. Immediately after the Norman conquest of England, King William installed one of his most trusted confidants, William FitzOsbern, as Earl of Hereford. By 1071 he had started the building of Chepstow Castle, the first castle in Britain built of stone, near the mouth of the Wye. It served as a base from which the Normans continued to expand westward into south Wales, establishing a castle at Caerleon and extinguishing the Welsh kingdom of Gwent. William also installed Roger de Montgomerie at
Hay-on-Wye Hay-on-Wye Hay-on-Wye ( or just "Y Gelli"), often abbreviated to just "Hay", is a small market town and community in the historic county of Brecknockshire (Breconshire) in Wales, currently administered as part of the unitary authority of Powys. With over twenty bookshops, it is often described as "the town of books", and is both the National Book Town of Wales and the site of the annual Hay Literary Festival. The settlement's name is first referred to between 1135 and 1147 as "Haya"; in 1299 the name of "La Haye" is used. By the 16th century it was simply called "Hay",