In an attempted negotiation of peace the emperor Valerian was captured by his enemy Sapor I, the king of Iran.
Citation:
Bouchard, Elsa. "Capture and death of Valerian".
The Literary Encyclopedia. First published 01 March 2010
[http://www.litencyc.com/php/stopics.php?rec=true&UID=11518, accessed 21 May 2013.]