The third New York Provincial Congress convened in Fishkill in May 1776. Fishkill became part of one of the largest colonial military encampments during the Revolutionary War. General Washington's aide-de-camp Alexander Hamilton took residence here. The Trinity Church, on Hopewell Avenue in the village, was organized in 1756 and the structure built in 1760. It was used as a hospital during the Revolutionary War. The Dutch Reformed church was used as a military prison. American spy Enoch Crosby was held there briefly with Loyalist recruits before beig allowed to escape.