200 years ago Secularization changed the German Southwest. Following the Napoleonic wars, the buildings, landholdings and property of the monasteries and bishoprics passed into state ownership. The repercussions are felt up until today, as new uses had to be found repeatedly for most of the empty buildings. The Palace of the Teutonic Order (Deutschordensschloss) in Mergentheim was also affected by the closure of religious institutions and the takeover of church property.
During Secularization in 1803 Württemberg troops dispossessed the Palace of the Teutonic Order. Two years later "all possessions of the Teutonic Order Deutschorden) in our country“ were acquired by the Württemberg electors by means of an independent decree. However, in the same year Napoleon assigned the property of the Order as the Principality of Mergentheim including its rights and income to the Austrian Emperor.
With the disbanding of the Teutonic Order in 1809, the courtly splendor of the residential palace of the Teutonic Order came to an end after 300 years. Since that time the Order's headquarters have been located in Vienna. Shortly before Napoleon promised Mergentheim to the Kingdom of Württemberg in 1809, "... His Majesty the King of Württemberg had the Principality of Mergentheim and all its residents [...] militarily occupied.“ The population reacted strongly, "The Württemberg troops were disarmed, the Württemberg coat of arms was torn down...“. A bloody end was put to the revolt.
Württemberg secularized all possessions of the Teutonic Order in Mergentheim. Large parts of the valuable library and the interior appointments were moved to Stuttgart and Ludwigsburg. The eventful history of use then began. From 1827 Duke Paul of Württemberg and his wife lived in the palace. He brought back zoological, mineralogical and botanical treasures from this journeys to far-away places and exhibited them in the palace. Some of those objects can be found in the Lindenmuseum in Stuttgart today. In 1868 the palace was furnished as a barracks for a battalion of infantrymen.
During the Third Reich local nazi party offices used the buildings. Directly following WWII emergency housing was set up for foreigners displaced in the war. Up into the '60s there was a clothing factory in the former palace chambers. Classrooms, the city administration, the city library and even a ballet school were housed here. Since extensive restoration measures in 1996, the palace has been completely accessible to the public as the Museum of the Teutonic Order (Deutschordensmuseum). It covers history, art, culture and the activities of the Teutonic Order.