[1]: 47–48 An earlier Romanesque basilica from the 12th century stood in the place of the current church as part of an ensemble of ecclesial buildings, including a graveyard and administrative structures.

[2] In the late 17th century, Kaspar Friedrich Nachtenhöfer [de], a writer of hymns, was parson and deacon at St Moriz.

The interior of the late Gothic hall church was refurbished in Baroque style in the middle of the 18th century.

[1]: 16 The church served as the burial place of the Ducal family until it became too small and a new mausoleum on the Friedhof am Glockenberg [de] was constructed in the 1850s, with financial support from the Royal houses of Belgium and the United Kingdom.

It is dominated by the 13 m (47 ft) high Renaissance alabaster epitaph for Duke Johann Friedrich II, by sculptor Nikolaus Bergner (finished in 1598).

[2][4] The organ by the Karl Schuke Berliner Orgelbauwerkstatt was installed in 1989 into a reconstructed frame originally built by Wolfgang Heinrich Daum (1740).