Byzantine Empire /
Full name: Gaius Flavius Valerius Aurelius Constantinus
To him, the beginning of the Byzantine Empire is attributed. This is illogical in the sense that he was the ruler of a united Roman Empire, but it is logical from two facts: He had former Bysants constructed into a great imperial capital named Constantinople, and it was rulers of his dynasty that gradually would form the dynasty ruling from here.
Constantine's rise to power came in a period of confusing politics. Emperors came ans went in the Roman Empire in the early 300's, and at one time, the empire had 4 contesting emperors. Constantine spent most of his reign to secure full control of the entire empire.
With him, Christianity is transformed into the preferred religion of the state. Whether Constantine himself was a Christian, or if he used the popularity of Christianity to aid his political goals, is a matter of understanding the sources. He is reported to have stated that he was aided by the Christian God, and is believed by many that the story of him being baptized shortly before his death, is a true story.
Yet, Constantine appears to have been closely linked to traditional Roman religions throughout his life, and the story of the above-mentioned baptizim have clear legendary elements, clearly making it questionable. Also, even after Christianity was made state religion, support for Roman religions continued. It may actually appear that Constantine adhered to some aspects of Christianity without having embraced the full Christian faith, or at least that the full conversion happened only first at the end of his life. Early on, he linked the Christian God with the sun god of Roman religion, yet, letters from him clearly indicate that at least he was not without some form of conviction.
Constantine played an important role in the development of Christian theology and its universal structure when convening the Council of Nicaea in 325.
Constantine regulated the laws to fit Christian interests, fx. was the penalty of crucifixion abolished, Sunday was made the holy day of the week and many privileges were introduced in favour of the clergy. In some cases, Roman sacred sites were turned into churches.
Constantine ordered the building of several churches, of which the original Hagia Sophia in Constantinople and St. Peter in Rome are among the most famous in Christian history.
Constantine imposed numerous regulations on the Jews; among which conversion from Christianity to Judaism was outlawed and Jewish entry to Jerusalem was strictly limited.
Constantine changed the organization of the rural areas, changing the free tenant farmers of the coloni into serfs, in which rights of the inidividual peasant were reduced.
On the home ground, Constantine's reign was one of great brutality, he was especially hard on all his political enemies.
The national administration rested with the emperor and his council. The senate had restored privilleges that had been taken away from it in the previous century.
Constantine won a long series of military victories. He had the Franks, Sarmatians and Goths defeated. He saw to the reorganization of the army, and completed the separation of civil and military authority.
Constantine is declared a saint with most Catholic and Orthodox churches, and eastern churches even call him the "13th apostle".