Deutschhaus Mainz

The Deutschhaus or Deutschordenskommende (German for "Commandry of the Teutonic Knights") is a historical building in Mainz, western Germany, which is the seat of the Landtag of Rhineland-Palatinate.

The building was constructed by Anselm Franz Freiherr von Ritter zu Groenesteyn in a style influenced by French Baroque architecture.

In the times of French occupation leading to the establishment of the Republic of Mainz, it became the seat of the Rhenish-German National Convention.

It was used as a palace by Napoleon during all of his 9 stays in Mainz, who planned to double the size of the building and use it as an imperial residence, as Mayence was intended to become one of the bonnes villes de l'Empire, the 36 most important cities of France.

In the aftermath of the Napoleonic Wars, the building was used by the Dukes of Hesse-Darmstadt, who obtained the territory of Mainz after the Congress of Vienna.