Editors. "The Duke of Guise surrenders Champagne to Henry IV". The Literary Encyclopedia. First published 01 February 2011
[http://www.litencyc.com/php/stopics.php?rec=true&UID=15472, accessed 25 May 2013.]
Henry IV gains control over Champagne when the Duke of Guise, stalwart of the Catholic League, gives it up to the newly recognised King of France.