George III of the United Kingdom

George III (George William Frederick; 4 June 1738 – 29 January 1820) was King of and  from 25 October 1760 until the unification of these two countries on 1 January 1801, and from then on was King of the United Kingdom until his death.

King George led Great Britain during the, where Britain stood victorious over France, and during the American Revolutionary War. During the latter conflict, the united thirteen colonies of Great Britain were lost and achieved their independence, becoming the United States.

Reference

 * Assassin's Creed III