This is a comprehensive study of the life of Zebulon Butler, a participant in the French and Indian War, the Revolutionary War, and the intercolonial confrontations known as the Yankee-Pennamite Wars. Butler migrated to Pennsylvania in 1769 and soon became the military and civil leader of the Connecticut settlers in the Wyoming Valley of Northeastern Pennsylvania. During the Revolutionary War, he served in one of the most dangerous theatres of the war—the isolated Susquehanna frontier of Pennsylvania—where the struggling settlers were subject to Indian-Tory attacks and the hostility of the Pennsylvania government. After the war, Butler sought peace with the Pennsylvania authorities and exercised a steadying influence on the Wyoming community. When the longstanding land controversy between Connecticut and Pennsylvania again erupted in civil war and sparked a separate state movement encouraged by Ethan Allen, Butler counseled peace and assisted Timothy Pickering in the establishment of Luzerne County.