Prudhoe Castle is built on a steep sided rocky outcrop above the River Tyne. The barony of Prudhoe was granted to Robert d'Umfraville by Henry I after 1100, and a new castle was constructed on the site of an earlier fortification. Odinel d'Umfraville, who succeeded his father in 1145, was brought up in the home of Earl Henry, father of the Scottish king, William the Lion. Odinel rejected any Scottish loyalty and supported the English king, Henry II, when William the Lion invaded northern England in 1173-4. The Scottish king besieged Prudhoe in 1173 and again in 1174, but was unsuccessful on both attempts. Odinel and his force eventually captured the Scottish king outside Alnwick, where William was forced to sign the treaty of Falaise, recognising Henry as the superior lord of Scotland.

The best preserved parts of this 12th century castle are the gatehouse and curtain wall. A stone keep was also built but this is now very ruinous. In the 13th century a barbican was constructed in front of the gatehouse. It was built on both sides of the moat and was connected by a drawbridge. The gatehouse was given a vaulted basement and a chapel was added on the first floor. The chapel sanctuary is built into an oriel window, said to be the earliest oriel window in any castle in northern England.

The male line of the Umfravilles came to an end in 1381 when Gilbert III died childless. His widow married Henry Percy, Earl of Northumberland, and following her death in 1398, the Percys gained possession of the castle. Although the castle remained inhabited it suffered from neglect and gradually fell into ruin. Between 1808 and 1818, Hugh Percy, 2nd Duke of Northumberland, repaired the outer wall and the great tower while the rest of the ruined buildings within the outer ward were demolished. A new manor house was built across the middle of the castle, replacing a late 13th century residential range.