The Edict of Thessalonica, also known as All Nations, was decreed by the Roman Emperor Theodosius on February 27, 380 (after Christ). Through this edict, Christianity became the official religion of the Roman Empire. With this edict, the Roman Empire in its entirety happened to have a new official religion after centuries of freedom of worship. The Roman Pantheon had been complemented over many centuries with the gods, deities and domestic lares, with the cult of their own ancestors and even with pre-Roman divinities that had been assimilated after the process of Romanization in many parts of the Empire. All this must now be abandoned to embrace the cult of a monotheistic religion and the moral norms that accompanied it. Despite this, Theodosius protected the now semi-clandestine from the persecution and harassment of Christians as far as he could.
The edict was given on the third day of the Kalendas of March in Thessalonica, in the fifth consulate of Gratian Augustus and first of Theodosius Augustus, which was entitled "EDITOR OF THE EMPERORS GRACIANO, VALENTINIAN (II) AND TEODOSIO AUGUSTO, TO THE PEOPLE OF THE CITY OF CONSTANTINOPLA "
"We want all the peoples who are governed by the administration of our clemency to profess the religion that the divine apostle Peter gave to the Romans, which until today has been preached as he himself preached, and which is evident by the pontiff Damaso and the Bishop of Alexandria, Peter, a man of apostolic holiness. That is, according to the apostolic doctrine and the evangelical doctrine we believe in the unique divinity of the Father, the Son and the Holy Spirit under the concept of equal majesty and of the pious Trinity. We ordain that they have the name of Catholic Christians who follow this norm, while others judge them insane and crazy about whom the infamy of heresy will weigh. Their places of assembly will not receive the name of churches and will be the object, first of divine vengeance, and then they will be punished by our own initiative that we will adopt following the heavenly will. "
However, the Church did not benefit at all from this formalization of the cult. As the highest authority of the Empire, Theodosius included the priesthood in the civil service of the same, which in practice placed them under his authority. Generating problems, and the death of about six thousand people, finally, The emperor was mocked in public by the Bishop of Milan, denying him this entry into the church. After a long penance, and as compensation, the emperor decreed in 392 the prohibition of pagan sacrifices.
The most likely thing is that very few of us knew that this happened on a day like today, February 28, hehe, I hope you like to vote and follow me @silene65 ; do not forget to VOTE XD, it is worth noting that I inform you and use the theories of this web page you can visit if you like https://es.wikipedia.org/wiki/Edicto_de_Tesalónica