William FitzWilliam, 1st Earl FitzWilliam (circa 1748–1833), was a prominent British politician and nobleman. He served as a member of the Whig Party and held various important positions, including Lord Lieutenant of Ireland from 1795 to 1801. His tenure was marked by efforts to address social and political issues in Ireland during a turbulent period. FitzWilliam was born into a wealthy family and inherited significant estates, which contributed to his influence. He was created the Earl FitzWilliam in 1797, reflecting his status in British society. His legacy includes contributions to both politics and the management of his estates in Yorkshire.