Alan Ian Percy (17 April 1880 – 23 August 1930) known as the 8th Duke of Northumberland from 1899, was a Conservative Party politician.
His father, 7th Duke of Northumberland, was an alderman on the Middlesex County Council. Despite the 'Northumberland' title, the Dukes, with their seat at Syon House, near Isleworth, were some of the largest landowners in the county. When he died in May 1918 the county council took the unusual step of electing him to be alderman in his father's place.
On 27 April 1921 he resigned his place on the council as he was no longer able to attend meetings.