- He was the son of Arthur Forbes, 2nd Earl of Granard and Mary Rawdon
He was commissioned before 1706, in the service of the Royal Navy.
He was invested as a Privy Counsellor (P.C.) [Ireland] in 1721.
He held the office of Member of Parliament (M.P.) (Whig) for Queenborough, Kent between 1723 and 1727. On 27 February 1725/26 he was called up to the House of Lords as Lord Forbes, although his father did not possess this title.
He was Commander-in-Chief of the Caribbean between September 1729 and December 1729.
He held the office of Plenipotentiary to the Court of Muscovy in 1733.
He gained the rank of Rear-Admiral in 1734.
He succeeded to the title of 4th Baronet Forbes, of Castle Forbes, Co. Longford, Ireland [N.S., 1628] on 24 August 1734. He succeeded to the title of 3rd Baron Clanehugh, co. Longford [I., 1675] on 24 August 1734. He succeeded to the title of 3rd Earl of Granard [I., 1684] on 24 August 1734. He succeeded to the title of 3rd Viscount of Granard, co. Longford [I., 1675] on 24 August 1734.
He gained the rank of Vice-Admiral in 1735.
He held the office of Member of Parliament (M.P.) (Whig) for Ayr Burghs between 1741 and 1747.
He has an extensive biographical entry in the Dictionary of National Biography.
Children of Vice-Admiral George Forbes, 3rd Earl of Granard and Hon. Mary Stewart
1. Lady Mary Forbes  d. 27 Nov 1797
2. Lt.-Gen. George Forbes, 4th Earl of Granard+ b. 15 Mar 1710, d. 16 Oct 1769
3. Admiral Hon. John Forbes+ b. 1714, d. 10 Mar 1796
1. [S37] Charles Mosley, editor, Burke's Peerage, Baronetage & Knightage, 107th edition, 3 volumes (Wilmington, Delaware, U.S.A.: Burke's Peerage (Genealogical Books) Ltd, 2003), volume 2, page 1628. Hereinafter cited as Burke's Peerage and Baronetage, 107th edition.
2. [S6] G.E. Cokayne; with Vicary Gibbs, H.A. Doubleday, Geoffrey H. White, Duncan Warrand and Lord Howard de Walden, editors, The Complete Peerage of England, Scotland, Ireland, Great Britain and the United Kingdom, Extant, Extinct or Dormant, new ed., 13 volumes in 14 (1910-1959; reprint in 6 volumes, Gloucester, U.K.: Alan Sutton Publishing, 2000), volume IX, page 240. Hereinafter cited as The Complete Peerage.
From the Dictionary of the National Biography: