On 6 February, France signed a treaty of aid with the United States. Thereafter, it sent its fleet to the North American continent. On 18 June, the British evacuated Philadelphia as a consequence.
Richert, Lucas Paul. "U.S.-France Treaty". The Literary Encyclopedia. First published 01 February 2009
[http://www.litencyc.com/php/stopics.php?rec=true&UID=5921, accessed 20 April 2014.]