List of Famous people named William

William Battie was an English physician who published in 1758 the first lengthy book on the treatment of mental illness, A Treatise on Madness, and by extending methods of treatment to the poor as well as the affluent, helped raise psychiatry to a respectable specialty. He was President of the Royal College of Physicians in 1764.

William Wigram was an English Member of Parliament for Irish constituencies.

William Edward Rootes, 1st Baron Rootes GBE was a British motor manufacturer. He opened his first car sales agency in 1913, leading to the global Rootes Group. During the Second World War he supervised the volume manufacture of aircraft and engines, as well as the supply of military motor vehicles and armoured fighting vehicles. He was knighted in 1942 for these services and for organising the reconstruction of bomb-damaged Coventry after its saturation bombing by the Luftwaffe on 14–15 November 1940. In the 1950s, he became a leader of Britain's export drive, and chaired a committee to found the University of Warwick with a vision of academic links with industry.

William Douglas, 8th Earl of Douglas, 2nd Earl of Avondale was a late Medieval Scottish nobleman, Lord of Galloway, and Lord of the Regality of Lauderdale, and the most powerful magnate in Southern Scotland.

William called William the Younger was duke of Brunswick-Lüneburg and ruled over the Wolfenbüttel and Göttingen principalities.