The title Duke of Northumberland was created in 1551 for John Dudley.
He supported the claim of his daughter-in-law, Lady Jane Grey, to the English throne, but when she was deposed by Queen Mary, Dudley was convicted of high treason and executed. George Fitzroy was awarded the title in 1674, but it became extinct as Fitzroy left no heirs. The title was created for the third time in 1766, and it has been in the Percy family ever since. The seat of the Dukes of Northumberland is Alnwick Castle, in Alnwick, Northumberland; their London residence is Syon House in Brentford.
The subsidiary titles of the Duke of Northumberland are: Earl of Northumberland (created 1749), Earl Percy (1766), Earl of Beverley (1790), Baron Warkworth (1749) and Baron Lovaine of Alnwick (1784). All titles are in the Peerage of Great Britain. The courtesy title of the eldest son and heir to the Duke is Earl Percy.
Dukes of Northumberland, First Creation (1551)
Dukes of Northumberland, Second Creation (1674)
Earls of Northumberland (1749)
- Algernon Seymour, 7th Duke of Somerset (1684-1750)
- Hugh Percy, 2nd Earl of Northumberland (1714-1786) (became Duke of Northumberland in 1766)
Dukes of Northumberland, Third Creation (1766)
- Hugh Percy, 1st Duke of Northumberland (1714-1786)
- Hugh Percy, 2nd Duke of Northumberland (1742-1817)
- Hugh Percy, 3rd Duke of Northumberland (1785-1847)
- Algernon Percy, 4th Duke of Northumberland (1792-1865)
- George Percy, 5th Duke of Northumberland (1778-1867)
- Algernon George Percy, 6th Duke of Northumberland (1810-1899)
- Henry George Percy, 7th Duke of Northumberland (1846-1918)
- Alan Ian Percy, 8th Duke of Northumberland (1880-1930)
- Henry George Alan Percy, 9th Duke of Northumberland (1912-1940)
- Hugh Algernon Percy, 10th Duke of Northumberland (1914-1988)
- Henry Alan Walter Richard Percy, 11th Duke of Northumberland (1953-1995)
- Ralph George Algernon Percy, 12th Duke of Northumberland (b. 1956)
his son and heir: George Dominic Percy, Earl Percy (b. May 4 1984)
