Tower

Caerphilly Castle was built in the second half of the 13th century, as part of the Anglo-Norman expansion into South Wales. The Normans began to make incursions into Wales from the late 1060s onwards, pushing westwards from their bases in recently occupied England. Their advance was marked by the construction of castles and the creation of regional lordships. The task of subduing the region of Glamorgan was given to the earls of Gloucester in 1093; efforts continued throughout the 12th and early 13th centuries, accompanied by extensive fighting between the Anglo-Norman lords and local Welsh rulers. The powerful de Clare family acquired the earldom in 1217 and continued to attempt to conquer the whole of the Glamorgan region.

Caerphilly Castle seen from the west
In 1263, Gilbert de Clare, also known as "Red Gilbert" because of the colour of his hair, inherited the family lands. Opposing him in Glamorgan was the native Welsh prince Llywelyn the Last. Llweyln had taken advantage of the chaos of the civil war in England between Henry III and rebel barons during the 1260s to expand his power across the region. In 1265 Llywelyn allied himself with the baronial faction in England in exchange for being granted authority over the local Welsh magnates across all the territories in the region, including Glamorgan. De Clare believed his lands and power were under threat and allied himself with Henry III against the rebel barons and Llywelyn.