Editors. "The Catholic League and the Protestant Union sign an agreement". The Literary Encyclopedia. First published 01 February 2011
[http://www.litencyc.com/php/stopics.php?rec=true&UID=15842, accessed 12 December 2013.]
In Germany, the two opposing groups of princes, the Catholic League and the Protestant Union, sign an agreement at Mülhausen. The princes of the League promise not to seize or attack the lands of the Protestant administrators of the Empire, or the secularised lands in north Germany, 'so long as the holders still act as loyal subjects of the Emperor'.