George III of the United Kingdom

George III (4 June 1738 – 29 January 1820), sometimes known by his birth name of George William Frederick, was King of and  from 25 October 1760, until the unification of those two states on 1 January 1801. Following this, he became King of the United Kingdom, which he remained as until his death.

King George led Great Britain during numerous conflicts, including the French and Indian War, where Britain stood victorious over France, and the later American Revolutionary War. It was in the latter that the Thirteen Colonies of America which Great Britain had accumulated were lost to George and subsequently achieved their own independence, becoming the United States.

Reference

 * Assassin's Creed III