How a persecuted sect became the biggest landowner in the West
Within three centuries Christianity went from a small Jewish movement to the Roman Empire's state religion. Constantine's gifts of land, cash and tax breaks were so generous that by the 6th century the Church owned more land than anyone else in the West, much of it paid for by taxing pagan cults.
Catholic tradition dates the Church to Pentecost in Jerusalem and holds that Peter led the Roman community, beginning an unbroken line of bishops of Rome that runs to Pope Leo XIV. Scholars debate how literally to take that. Many think Rome was run by a group of presbyters until the mid-2nd century, with the title bishop of Rome later applied backwards. Protestant theologians such as Oscar Cullmann doubt a formal link between Peter and the papacy, while Catholic scholar Raymond E. Brown argues Peter's roles shaped the office anyway.
The empire's roads, the relative safety of the Pax Romana and a shared Greek language made spreading ideas easier. By 100 AD there were more than 40 Christian communities, some as far away as Armenia, Iran and India's Malabar Coast. Converts came first from slaves and the urban poor, then aristocratic women. Around 50 the Council of Jerusalem ruled that Gentiles need not keep all of the Mosaic Law, and the break from Judaism was virtually complete when Christians refused to join the Bar Kokhba revolt of 132.
Refusing all other gods set Christians apart from public festivals, and rumours about their closed gatherings fed hostility. Persecution was mostly local and sporadic until late 3rd-century emperors blamed the empire's crises on angry gods and ordered universal sacrifice. Estimates of those executed range from a few hundred to 50,000, and quarrels over how to treat those who had renounced the faith produced lasting splits.
Constantine credited his victory in 312 to the Christian God, and the Edict of Milan in 313 granted toleration; by 380 Christianity was the state religion. Worried that about half of Christians followed non-mainstream versions, he began calling ecumenical councils to settle doctrine. Centuries later the East-West Schism divided Greek and Latin churches, and the Second Vatican Council of the 1960s brought the largest changes since Trent.
Source: History of the Catholic Church
