Numerous cities such as Athens, Thebes and Corinth engaged in hostilities with Sparta, whose widespread activities in Greece and Asia had become threatening.
Citation:
Bouchard, Elsa. "Corinthian War".
The Literary Encyclopedia. First published 01 March 2010
[http://www.litencyc.com/php/stopics.php?rec=true&UID=11249, accessed 19 June 2013.]