The Great Awakening refers to a number of periods of religious revival in American Christian history. Historians and theologians identify three, or sometimes four, waves of increased religious enthusiasm between the early 18th century and the late 20th century. Each of these "Great Awakenings" was characterized by widespread revivals led by evangelical Protestant ministers, a sharp increase of interest in religion, a profound sense of conviction and redemption on the part of those affected, an increase in evangelical church membership, and the formation of new religious movements and denominations.