in 1529 by Henry Percy, 15th Earl of Northumberland from Robert Radclyffe, 1st Earl of Sussex (1483–1542). Leconfield Castle, Yorkshire. Syon House, Isleworth, Middlesex, the former Syon Monastery, acquired in 1594 by Henry Percy, 9th Earl of Northumberland (1564-1632). Following the death of his grandson Algernon Seymour, 7th Duke of Somerset in 1750, the former Percy estates were split between the Smithson ("Percy", Duke of Northumberland) and Wyndham (Earl of Egremont) families See also Percy (surname) Percy (given name) Percy (disambiguation) References 1067 establishments in England Anglo-Norman families English families Noble families of the United Kingdom