Hugh le Despenser, 1st Baron le Despenser, Lord of Glamorgan, was an English peer. Imprisoned as a consequence of his support for deposed king Edward II, he would return to royal favour under Edward III, being made Baron le Despenser in 1338. His title became extinct at his death without issue.

The Lordship of Glamorgan was one of the most powerful and wealthy of the Welsh Marcher Lordships. The seat was Cardiff Castle. It was established by the conquest of Glamorgan from its native Welsh ruler, by the Anglo-Norman nobleman Robert FitzHamon, feudal baron of Gloucester, and his legendary followers the Twelve Knights of Glamorgan. The Anglo-Norman Lord of Glamorgan, like all Marcher lords, ruled his lands directly by his own law: thus he could, amongst other things, declare war, raise taxes, establish courts and markets and build castles as he wished, without reference to the Crown. These privileges were only lost under the Laws in Wales Acts 1535–1542. Though possessing many castles, the main seat of the Lordship was Cardiff Castle.