The Tractarians postulated the Branch Theory, which states that Anglicanism along with Eastern Orthodoxy and Roman Catholicism form three "branches" of the historic pre-schism Catholic Church. Tractarians argued for the inclusion of traditional aspects of liturgy from medieval religious practice, as they believed the church had become too "plain". In the final tract, "Tract 90", Newman argued that the doctrines of the Roman Catholic Church, as defined by the Council of Trent, were compatible with the Thirty-Nine Articles of the 16th-century Church of England. Newman's eventual reception into the Roman Catholic Church in 1845, followed by Henry Edward Manning in 1851, had a profound effect upon the movement.