The British held off Defending a Franco-American siege in 1779 , and held Defending the city until late in the war .

The siege Besieging itself consisted Cause_to_be_included of a joint Franco-American attempt to retake Conquering Savannah , from September 16 to October 18 , 1779 .

The French were able to achieve Achieve control Control of the sea lanes against the British and provided Supply the Franco-American army with siege Besieging artillery and French reinforcements Cause_change_of_strength .