when was the term roman catholic church first used
Roman Catholic (term) The term "Roman", as in the "Roman Church", has been used since the Middle Ages – often connoting the local particular church of the Diocese of Rome – the first known occurrence of "Roman Catholic" as a synonym for "Catholic Church" was in communication with the Armenian Apostolic Church in 1208, after the East–West Schism.[3][4]
Constantine the Great and Christianity Constantine's decision to cease the persecution of Christians in the Roman Empire was a turning point for early Christianity, sometimes referred to as the Triumph of the Church, the Peace of the Church or the Constantinian shift. In 313, Constantine and Licinius issued the Edict of Milan decriminalizing Christian worship. The emperor became a great patron of the Church and set a precedent for the position of the Christian emperor within the Church and the notion of orthodoxy, Christendom, ecumenical councils, and the state church of the Roman Empire declared by edict in 380. He is revered as a saint and isapostolos in the Eastern Orthodox Church, Oriental Orthodox Church, and various Eastern Catholic Churches for his example as a "Christian monarch."