Protestant Union

The Protestant Union (also known as Evangelical Union or Union of Auhausen) was a coalition of Protestant German states that was formed in 1608 to defend the rights, lands and person of each member.It was formed after the Holy Roman Emperor tried in 1607 to reestablish Catholicism in Donauwörth and after a majority of the Reichstag decided that the renewal of the Peace of Augsburg of 1555 should be conditional upon the restoration of all church land appropriated since 1552. The Protestant Princes met in Auhausen, near Nördlingen and on May 14 1608 formed a military league under the leadership of Frederick IV of the Palatinate. In response, the Catholic League was formed in the following year, headed by Duke Maximilian I of Bavaria.
See more at Wikipedia.org...