Hanover or Hannover (German: Hannover (help·info), [haˈnoːfɐ]), on the river Leine, is the capital of the federal state of Lower Saxony (Niedersachsen), Germany and was once by personal union the family seat of the Hanoverian Kings of Great Britain, in their dignities as the dukes of Brunswick-Lüneburg (which title was later called the Elector of Hanover at the end of the historical period known as Early Modern Europe). After the Napoleonic Wars ended, the Electorate was enlarged and made into the capital of the Kingdom of Hanover.

In addition to being the capital of Lower Saxony, Hanover was the capital of the administrative area Regierungsbezirk Hannover (Hanover region) until Lower Saxony's administrative regions were disbanded at the beginning of 2005. It is, however, still part of the Hanover district (Region Hannover), which is a municipal body made up from the former district and city of Hanover.

With a population of 522,944 (1 February 2007) the city is a major center of northern Germany, known for hosting annual commercial expositions such as the Hanover Fair and the CeBIT. Every year Hanover hosts the Schützenfest Hannover, the world's largest Marksmen's Fun Fair, and the Oktoberfest Hannover, which is the second largest Oktoberfest in the world. In 2000, Hanover hosted the world fair Expo 2000. The Hanover fairground, due to numerous extensions, especially for the Expo 2000, is the largest in the world. Hanover also has regional importance because of its universities and medical school, its international airport, and its large zoo. The city is also a major crossing point of railway lines and highways (Autobahnen), connecting European main lines in east-west-direction (Berlin - Ruhr area) and north-south-direction (Hamburg - Munich et al.).