The two most prolific groups ever to split from the Catholic Church have been the Eastern Orthodox and Protestant churches. The two groups left Catholicism more than four centuries apart and for very different reasons. Because Protestantism began in the West, dialogue between the two groups has been relatively infrequent until modern times.
Medieval Roman Catholic Traditions The Roman Catholic Church, is the oldest and largest Christian congregation in the world dating about two thousand years and with more than 1.16 billion believers worldwide. The Catholic Church has at the top of its hierarchy the papacy, and the person at the seat of Papacy is called the Pope.1.