The Rev., afterwards Sir, William Palmer, Bart., of Worcester College, University of Oxford, was an early supporter and influence in the Oxford Movement, but was superseded by John Henry Newman and Edward Pusey. Palmer initially supported the Tracts for the Times, but as opposition to the Oxford Movement grew, he withdrew his support, prompting a cooling in his friendship with Newman and a slow decline in his involvement with the movement.
Palmer was author of the Origines Liturgicæ and Treatise on the Church of Christ (1838). The latter formulated the notion, called the "Branch Theory" that, provided that both the apostolic succession, and the Faith of the Apostles are kept intact, then there the Church exists, albeit in one of its branches. This was applied to the Anglican Church.