The Christian Association of Washington was an organization established by Thomas Campbell in 1809 to promote Christian unity. It was a study group that Campbell formed with like minded friends and acquaintances in the local neighborhood of Washington, Pennsylvania. The group sought to foster unity by focusing on a common form of Christianity that they could all agree upon. This charter that Campbell wrote for this group, the Declaration and Address of the Christian Association of Washington, became one of the most important early texts of the Restoration Movement.