Editors. "Diet of Speyer meets". The Literary Encyclopedia. First published 01 November 2010
[http://www.litencyc.com/php/stopics.php?rec=true&UID=14694, accessed 24 May 2013.]
At a meeting of the Diet of Speyer, the German Lutheran princes concede to vote supplies to fund the Emperor's wars with France and Turkey. In return, Charles V is obliged to leave open the question of a national religious settlement in Germany.