Sir George Makgill, 11th Baronet (24 December 1868 in Stirling – 16 October 1926 in London) was a Scottish novelist and right-wing propagandist.
George Makgill was the son of Captain John Makgill and Margaret Isabella Haldane, sister of Lord Haldane. Educated privately, Makgill lived for several years in New Zealand where his father had a station at Waiuku. In 1891 he married Frances Elizabeth Grant of Merchiston, Otago. After his father died in 1906, Makgill established his claim to the Baronetcy of Makgill, and continued to petition for the revival of the Lordship and Viscountcy of Oxfuird. As Sir George Makgill, he settled in Eye, Suffolk, leasing Yaxley Hall, an Elizabethan mansion, from Lord Henniker.
During the First World War Makgill was Secretary to the Anti-German Union, later renamed the British Empire Union. In 1915 and 1916 he brought a lawsuit to strip the German-born banker Ernest Cassel and American-born of German parents railway financier Edgar Speyer of their Privy Council membership: though the case was dismissed, Edgar Speyer's English citizenship was stripped after the war. After the war business interests invited him to set up a private intelligence network, the Industrial Intelligence Board, to monitor communists, trade unionists and industrial unrest. Amongst the IIB's agents were Maxwell Knight and John Baker White, who later characterized Makgill as "perhaps the greatest Intelligence officer produced in this century"
In 1920 he announced himself as a People's League parliamentary candidate for East Leyton., and in 1921 as an Anti-Waste League candidate. He became General Secretary of the Empire Producers' Organization. He was also a member of the Anti-Socialist Union and was for a time part of a tendency within that group close to the British Fascists.