Galba's murder was contrived by Otho whose hopes of being declared his heir had been disappointed. Otho's new emperorship was rejected by the partisans of Vitellius, who decisively defeated Otho a few months later (April 69).
Bouchard, Elsa. "Murder of Galba". The Literary Encyclopedia. First published 01 March 2010
[http://www.litencyc.com/php/stopics.php?rec=true&UID=11437, accessed 24 May 2013.]