John Sigismund's break with the Lutheran Church

IN THE MARK Brandenburg, the elector John Sigismund, though with an oath he promised his father Joachim Frederick to remain loyal to the Lutheran Church, broke faith in 1613, when on Christmas day he formally entered the Reformed Church. The Augsburg Confession (variata) was retained, but in 1614, the Elector introduced a Calvinistic Confession of his own, the Confessio Marchica, in which the doctrine of absolute predestination was omitted. He could not however get his people to follow him and when radical measures were resorted to, a violent uprising of the masses occurred, which resulted in bloodshed (1615). In 1616, the professors at Frankfort-on-the-Oder were forbidden to teach the communicatio idiomatum and ubiquitas corporis. He also forbade students going to Wittenberg, and finally ordered the formula Concordia to be stricken from the collection of Lutheran symbolical books.

The failure to Calvinize Lutheran countries in this manner, suggested another slower, but surer way, that of union. An agreement was to be reached by means of colloquiums…

(From H.E. Jacobs, The Lutheran Cyclopedia.)