Catholicism had control of western Christianity from its foundation In 1517 the German monk Martin Luther pinned his 95 Theses to the door of his Catholic church, denouncing the Catholic sale of indulgences — pardons for sins — and questioning papal authority. This led to his excommunication and the start of the Protestant Reformation and a split church.
The Papal States where were the Catholic Pope held direct “temporal” authority in central Italy. They began in the middle of the eighth century, and ended with the unification of Italy in 1870. Today the Pope has authority only over the Vaitcan City which is part of Rome.)
During the early history of Christianity, Rome became an increasingly important center of the faith, which gave the bishop of Rome (the Pope) more power over the entire church, thereby ushering in the era of papal supremacy.
When Catholicism became the official religion of the Roman Empire in 380, the power of the Pope increased, although he was still subordinate to the Emperor.
After the fall of the Western Roman Empire, the Pope served as a source of authority and continuity; however, for several centuries afterward the Eastern Roman Emperor still maintained authority over the church.
From the late-6th to the late-8th century there was a turning of the papacy to the West and an escape from subordination to the authority of the Byzantine Emperors of Constantinople.
When Pope Leo III crowned Charlemagne as Roman Emperor in 800, he established the precedent that, in Western Europe, no man would be Emperor without being crowned by a Pope.
After a conflict known as the Investiture Controversy, as well as from the launching of the Crusades, the papacy increased its power in relation to the secular rulers of Europe.
Throughout the Middle Ages, popes struggled with monarchs over power.
PARTIAL LIST OF PAPAL BULLS AND OTHER RELEVANT DOCUMENTS ON THE JEWISH QUESTION (from Catholicism)
(Editor’s Note A papal bull is a type of public decree, letters patent, or charter issued by a Pope of the Catholic Church. It is named after the leaden seal (bulla) that was traditionally appended to the end in order to authenticate it.