Mittelsinn is a community in the Main-Spessart district in the Regierungsbezirk of Lower Franconia of Würzburg had passed by 1808 to the Principality of Aschaffenburg (in 1803 first to Bavaria, and then in 1805 to the Grand Duchy of Würzburg), with which it passed in 1814 to Bavaria. The local rights held by the Electorate of Hesse-Kassel, however, did not pass to Bavaria until 1860. In the course of administrative reform in Bavaria, the current community came into being with the Gemeindeedikt (“Municipal Edict”) of 1818.No later than the 19th century, there were Jewish families living in Mittelsinn who formed their own community and built a synagogue. This was destroyed on Kristallnacht (9 November 1938), as recalled by a memorial plaque at the savings and loan institution across the street from the synagogue’s former site.