Ostheim was first mentioned in 804. During the
Reformation, Ostheim (along with much of the surrounding region) became Protestant. However, in the 1580s and 1590s, a powerful Counter-Reformation effort led by
Julius Echter von Mespelbrunn, the
Prince-Bishop of
Würzburg, reconverted most of the Streutal (the
Streu valley, in northern Franconia) back to Catholicism. Ostheim and a few villages nearby became Protestant islands in a solidly Catholic region. (The town's heavily fortified Lutheran church dates from this period.) Ostheim was sacked by Imperial troops in 1634 during the
Thirty Years War, but survived and retained its distinctive character. From the 17th century until 1920 the town was an exclave of Protestant
Saxe-Weimar-Eisenach, first in Catholic Franconia and then in
Bavaria after Franconia came under the Bavarian crown. After the First World War, it became an
exclave of Thuringia in
Bavaria from 1920 until 1947. During the late 19th and early 20th century, as religious differences faded in importance, the town became increasingly integrated into the surrounding region, becoming a small regional industrial center as well as a market for the surrounding agricultural hinterland. In 1945 Ostheim became part of the American controlled zone, in the Free State of Bavaria. In 1947 it was formally transferred to Bavarian control in exchange for some similar exclaves in the Soviet Zone. Ostheim lies on the river Streu between
Mellrichstadt and
Fladungen. It is one of the stops in
Wim Wenders' 1976 road trip film
Kings of the Road. The gunmaking company
Herbert Schmidt Ostheim (also:
HS - Herbert Schmidt Waffentechnik) was based in Ostheim. It is also the home of German soft drink manufacturer
Bionade. Ostheim's historic architecture, walkable town center and easy access to the biking and hiking trails of the Streu valley have helped make it a local center for tourism. ==Landmarks==