Alexander Daniel Alan Macmillan, 2nd Earl of Stockton (born October 10 1943) is a Conservative Party politician in the United Kingdom. He was a member of the European Parliament for South West England from 1999 to 2004.

He was one of the hereditary peers to have been excluded from the House of Lords. He inherited his peerage from his grandfather, Harold Macmillan, 1st Earl of Stockton, who was Prime Minister of the United Kingdom from 1957 to 1963. He was an unsuccessful candidate in the by-election in 2007 to replace Lord Mowbray in the House of Lords, coming third behind the winner, Earl Cathcart and Viscount Younger.

Both his father Maurice Macmillan (1921-1984) and his grandfather preceded him as Chairman of Macmillan Publishers Ltd., the publishing house long owned by the family. The 2nd Earl sold it to the German Holtzbrinck group. He ranked 127th in the Sunday Times Rich List 2004, with an estimated wealth of £326m.

Marriages

• 1) Hélène Birgitte Hamilton, in 1970 and they were divorced in 1991. There were three children of this marriage:
  • Daniel Maurice Alan Macmillan, Viscount Macmillan of Ovenden (b. 9 October 1974)
  • Lady Rebecca Elizabeth Macmillan (b. 1980)
  • Lady Louisa Alexandra Macmillan (b. 1982)

• 2) Miranda Quarry, (the third wife of Peter Sellers), on 23 December 1995

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