Duke of Northumberland (1766)

==Holders==
 	From 	Until 	Name 	Lifespan
1. 	22 October 1766 	6 June 1786 	The Most Noble Hugh Percy, 1st Duke of Northumberland, K.G., P.C. 	1714-1786
2 	6 June 1786 	10 July 1817 	The Most Noble Hugh Percy, 2nd Duke of Northumberland, K.G. 	1742-1817
3. 	10 July 1817 	11 February 1847	The Most Noble Hugh Percy, 3rd Duke of Northumberland, K.G., P.C. 	1785-1847
4. 	11 February 1847	12 February 1865	The Most Noble Algernon Percy, 4th Duke of Northumberland, K.G., P.C. 	1792-1865
5. 	12 February 1865	22 August 1867 	The Most Noble George Percy, 5th Duke of Northumberland, P.C. 	1778-1867
6. 	22 August 1867 	2 January 1899 	The Most Noble Algernon George Percy, 6th Duke of Northumberland, K.G., P.C. 	1810-1899
7. 	2 January 1899 	14 May 1918 	The Most Noble Henry George Percy, 7th Duke of Northumberland, K.G., P.C. 	1846-1918
8. 	14 May 1918 	23 August 1930 	The Most Noble Alan Ian Percy, 8th Duke of Northumberland, K.G., C.B.E., M.V.O. 	1880-1930
9. 	23 August 1930 	21 May 1940 	The Most Noble Henry George Alan Percy, 9th Duke of Northumberland 	1912-1940
10.	21 May 1940 	11 October 1988 	The Most Noble Hugh Algernon Percy, 10th Duke of Northumberland, K.G., G.C.V.O., P.C.	1914-1988
11.	11 October 1988 	31 October 1995 	The Most Noble Henry Alan Walter Richard Percy, 11th Duke of Northumberland 	1953-1995
12.	31 October 1995 	present 	The Most Noble Ralph George Algernon Percy, 12th Duke of Northumberland 	1956-
==Other Titles Held==
===Peerage of Great Britain===
*Earl of Northumberland (1749), 1766-present
*Earl Percy (1766), 1766-present
*Earl of Beverley (1790), 1865-present
*Baron Percy (1723), 1786-1812, 1817-present
*Baron Warkworth (1749), 1766-present
*Baron Lovaine (1784), 1784-1786, 1865-1887, 1899-present
===Peerage of the United Kingdom===
*Baron Prudhoe (1816), 1847-1865
===Baronetage of England===
*Smithson baronets, of Stanwick, 1766-present