Hanover is the capital and largest city of the German state of Lower Saxony. Its 535,932 (2021) population makes it the 13th-largest city in Germany as well as the fourth-largest city in northern Germany after Berlin, Hamburg and Bremen. Hanover's urban area comprises the towns of Garbsen, Langenhagen and Laatzen and has a population of about 791,000 (2018). The Hanover Region has approximately 1.16 million inhabitants (2019) and is the largest in the Hannover–Braunschweig–Göttingen–Wolfsburg Metropolitan Region.

The Kingdom of Hanover 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 between 1714 and 1837. 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.