Abergavenny was the site of a Roman fortress (NPRN 306295), built to suppress the native population and occupied from around 57AD until the middle of the second century. A small community remained on the site, but the town did not develop in earnest until the arrival of the Normans in the eleventh century. In 1087 Hamelin de Ballon arrived in the region, and began work on the motte and bailey precursor of Abergavenny Castle (NPRN 94876), before founding St. Mary's Priory (NPRN 20703), and surrounding the whole with a ditch and embankment for protection, later replaced by a stone curtain (NPRN 306259). There was a period of intense hostility between the planted population of Abergavenny and the native Welshmen in the region, which culminated in 1175 in the massacre of Welsh nobles at the town's castle.

Abergavenny has survived a number of skirmishes throughout its history, including attack by Owain Glyndwr in 1404 (NPRN 404986), and attack by a parliamentarian force during the English Civil War, which led to the royalist townsmen blowing up the castle to render it useless to their attackers. Since that period the town has flourished through trade in a number of industries, including flannel weaving, tanning and goat-hair wig making. The town's market hall (NPRN 31977) stands as a testament to this market town's successful trading past.

K Steele, RCAHMW, 23 January 2009