Question: Jean-Joseph Sourbader de Gimat was part of a war in Yorktown Virginia with American and French allies that ended on what date?
Sentence (from "Battle of the Chesapeake"): The French were able to achieve control of the sea lanes against the British, allowing them to provide the Franco-American army with siege artillery and French reinforcements—all of which proved decisive in the Siege of Yorktown, effectively securing independence for the Thirteen Colonies.
Relevant evidence: No