From household meals to two billion adherents
Christianity began with Jesus, crucified in Jerusalem about 30–33 CE, and a few hundred early believers. By the year 100, roughly one hundred house churches averaged seventy members. Legalized under Constantine in 313, it is now the world’s largest religion, with more than two billion followers.
Jesus of Nazareth preached the coming kingdom of God in Galilee and Judea; his crucifixion around the year 30 is well attested even where other details stay debated. Followers proclaimed incarnation and resurrection, practiced baptism and communal Eucharist, and first gathered as Jews loyal to Jesus. Growth was urban and grassroots: under one thousand believers at the start, then over two hundred thousand by 200 CE and more than a million by 250, with bishops overseeing expanding networks. Women were numerous among early members and appear prominently in Pauline letters and art.
Paul, once a Pharisee who opposed the movement, became its traveling apostle after a Damascus experience. The Council of Jerusalem about 50 CE eased Gentile entry without full Mosaic law. Greek, Syriac, and Latin carried the message along trade routes from Antioch to Britain and Mesopotamia. Persecutions were usually local until mid-third-century empire-wide waves; Diocletian’s measures of 303–311 marked a peak. Constantine’s Edict of Milan in 313 extended toleration and showered churches with legal standing and funds.
Fourth-century councils such as Nicaea in 325 sought creed amid Christological disputes that later yielded lasting eastern divisions. Across two millennia the faith weathered Rome’s fall, medieval schism in 1054, crusades, inquisitions, Reformation splintering in the sixteenth century, and global missionary expansion. In the twentieth century it declined in much of the West while growing in the Global South; by the twenty-first it embraces over three thousand languages as the planet’s most plural large religion.
Source: History of Christianity
