The Kingdom of Hanover (German: Königreich Hannover) was established in October 1814 by the Congress of Vienna, with the restoration of George III to his Hanoverian territories after the Napoleonic era. It succeeded the former Electorate of Hanover, and joined 38 other sovereign states in the German Confederation in June 1815. The kingdom was ruled by the House of Hanover, a cadet branch of the House of Welf, in personal union with Great Britain since 1714. Since its monarch resided in London, a viceroy, usually a younger member of the British royal family, handled the administration of the Kingdom of Hanover. The personal union with the United Kingdom ended in 1837 upon the accession of Queen Victoria because semi-Salic law prevented females from inheriting the Hanoverian throne while a dynastic male was still alive. Her uncle Ernest Augustus thus became the ruler of Hanover. His only son succeeded him to the throne as George V. However, as he backed the losing side in the Austro-Prussian War, his kingdom was conquered by Prussia in 1866 and ceased to exist as an independent kingdom, becoming the Prussian Province of Hanover. Along with the rest of Prussia, Hanover became part of the German Empire upon the unification of Germany in January 1871. Briefly revived as the State of Hanover in 1946, the state was later merged with some smaller states to form the current state of Lower Saxony in West Germany. Source: Wikipedia (en)