The Illinois
Patrick Henry ordered Col. George Rogers Clark to take the Illinois country for Virginia in January 1778. Using Fort Pitt information and Spanish support secured by Henry, his Illinois Regiment surprised the largely French population at Kaskaskia, Cahokia, and Vincennes in July. After British governor, Henry Hamilton, brought a Detroit force to recapture Vincennes, Clark led his 170-man army through “a drowned country” in February 1779 to retake Vincennes and capture its commander. The British surrender of Vincennes survives among the most important events of the American Revolution, as it nullified the Crown’s plan to capture the American West before trapping Washington on the east coast. The new country’s ability to hold the territory through the Treaty of Paris negotiations also secured the Old Northwest territory for the United States.