Christianity spread throughout the early Roman Empire, despite persecutions due to conflicts with the pagan state religion. In 313, the struggles of the Early Church were lessened by the legalisation of Christianity by the Emperor Constantine I. In 380, under Emperor Theodosius I, Catholicism became the state religion of the Roman Empire by the decree of the Emperor, which would persist until the fall of the Western Empire, and later, with the Eastern Roman Empire, until the Fall of Constantinople. During this time, the period of the Seven Ecumenical Councils, there were considered five primary sees (jurisdictions within the Catholic Church) according to Eusebius: Rome, Constantinople, Antioch, Jerusalem, and Alexandria, known as the Pentarchy.