Ogmore is a hamlet to the north west of Ogmore by Sea. It sits on the banks of the River Ogmore in the Vale of Glamorgan, South Wales. Close by is the confluence of the Rivers Ogmore and Ewenny. Higher up stream the two rivers branch off in a 'V' shape leaving a piece of land in the middle between the rivers.

Legend has it that the famous Celtic chieftain King Arthur fought his last battle on this piece of land on the banks of the two rivers. The story states that he was fatally wounded and in order to keep the Kingdom together, his death was kept secret and his body laid in a cave in Coed y Mwstwr forest.

The history of Ogmore Castle goes back to Norman times. The Norman William de Londres built the first settlement, presumably a motte, here in 1116. In 1126 William's son Maurice de Londres added a rectangular stone tower to the fortification. The history of the castle from then onwards is very brief: the de Londres family owned Ogmore for some time, before it passed into the hands of Payn de Chaworth, lord of Kidwelly, late in the 13th century. In 1298 Matilda, the de Chaworth heiress, married Henry Earl of Lancaster and in consequence the castle became part of the Duchy of Lancaster, where it still remains today.