[2]: 20 In 1851, a committee headed by Prince August of Saxe-Coburg and Gotha set out to plan the construction of a Roman Catholic church.

[3] The church was opened on 28 August 1860 (Augustine of Hippo's feast day) by the Archbishop of Bamberg Michael Deinlein.

[1] On 15 July 1909, the Protestant Princess Beatrice of Saxe-Coburg and Gotha married the Roman Catholic Infante Alfonso, Duke of Galliera, in a civil ceremony at Schloss Rosenau, followed by a Roman Catholic religious ceremony at St. Augustin and a Lutheran one in Schloss Callenberg.

[2]: 20 Prince August and his wife, Princess Clémentine of Orléans, are buried in a double sarcophagus on the right side of the vault.

The remains of August and Clémentine's eldest son and Leopold Clemens' father, Prince Philipp, can also be found on the left side of the vault.