Martin Luther, summoned by Cardinal Cajetan (de Vio) to the Diet of Augsburg, refuses to recant. The Diet of Augsburg refuses to provide the Emperor with a subsidy for fighting the Turks.
Citation:
Editors. "Imperial Diet at Augsburg: Martin Luther presents his arguments against Catholicism".
The Literary Encyclopedia. First published 01 March 2010
[http://www.litencyc.com/php/stopics.php?rec=true&UID=9928, accessed 26 May 2013.]