|Succeeded by||Lower Saxony State Party|
The German-Hanoverian Party (German: Deutsch-Hannoversche Partei, DHP), also known as the Guelph Party (German: Welfenpartei), was a conservative, federalist political party in the German Empire and the Weimar Republic.
The party was founded in 1867 in protest of the annexation of the Kingdom of Hanover by the Kingdom of Prussia in the aftermath of the Austro-Prussian War. They wanted the revival of the Kingdom of Hanover and the restoration of the sequestrated assets of the former ruling House of Welf. The party therefore was also called the Welfen, and drew its strongest support from the rural areas around Hannover.
In the Reichstag DHP deputies usually acted as allies of the anti-Prussian Centre Party parliamentary group under Ludwig Windthorst, who although a Catholic and leader of the Centre Party was a former Hanoverian Justice Minister who was loyal to the House of Welf. From 1890 the party was led by Georg von der Decken.
During the German Revolution of 1918-1919, the DHP advocated the implementation of a Free State of Hanover within the Weimar Republic and succeeded in having a plebiscite held in the Prussian Province of Hanover on 19 May 1924. However, the referendum fell short of the one-third threshold required to enact devolution. The defeat hastened the party's decline and in the following years many members joined the rising Nazi Party, others the Catholic Centre. In 1933 the DHP, like other conservative and liberal parties, dissolved to prevent a ban by the Nazi regime.
After World War II, a party called Niedersächsische Landespartei ("Lower Saxon State Party") was formed as a continuation of the DHP. From 1947 that party was known as the German Party (DP). By the time of 1953, a group of DP dissidents formed a new DHP, which again joined the remnants of the German Party in 1962.