Nontrinitarianism (or antitrinitarianism) refers to theology that rejects the doctrine of the Trinity. Various nontrinitarian views, such as adoptionism or modalism, existed in early Christianity, leading to the disputes about Christology. 

 

      Nontrinitarianism later appeared again in the Gnosticism of the Cathars between the 11th and 13th centuries, among groups with Unitarian theology in the Protestant Reformation of the 16th century, in the 18th-century Enlightenment, and in some groups arising during the Second Great Awakening of the 19th century.