under the dominion of the Electorate of Mainz. Erfurt became part of the Kingdom of Prussia in 1802. In the Capitulation of Erfurt the city, its 12,000 defenders, and the Petersberg fortress were handed over to the French on 16 October 1806. The city became part of the First French Empire in 1806 as Principality of Erfurt, and was returned to Prussia in 1815 after the Napoleonic Wars. Although enclosed by Thuringian territory in the west, south and east, the city remained part of the Prussian Province of Saxony until 1944. The city was the site of the failed Erfurt Union of German states in 1850.
The Erfurt Program was adopted by the Social Democratic Party of Germany during its congress at Erfurt in 1891.
In 1914 The Erfurt Company JA Topf & Sons began the manufacture of crematoria later becoming the market leader in this industry. Under the Nazi's JA Topf & Sons supplied specially developed crematoria, ovens and associated plant to the death camps at Auschwitz-Birkenau and Mauthausen. On 27 January 2011 a memorial and museum dedicated to the Holocaust victims killed using Topf ovens was opened at the former company premises in Erfurt.
Bombed as a target of the Oil Campaign of World War II, Erfurt suffered only limited damage and was captured on 12 April 1945, by the US 80th Infantry Division. On 3 July, American troops left the city and the city became part of the Soviet Zone of Occupation and East Germany. On 19 March 1970 the East and West German Chancellors Willi Stoph and Willy Brandt met in Erfurt, the first such meeting since the division of Germany. After reunification, the city became the capital of the re-established state of Thuringia
