Study the life and accomplishments of the Roman Emperor Constantine I. Learn about why he is called Constantine the Great and how he legalized Christianity.
Updated: 11/21/2023
Constantine the Great | Biography, History & Accomplishments
Table of Contents
- Who was Constantine the Great?
- Early Life
- The Battle of the Milvian Bridge
- Constantine as Emperor
- Constantine, Christianity, and the Edict of Milan
- The Founding of Constantinople
- Lesson Summary
Constantine the Great was a Roman emperor who ruled from 306 to 337 CE. Constantine was the first Roman emperor to convert to Christianity, promoting tolerance for that religion; for that reason, he has been seen as a great ruler throughout Christian history. Constantine also accomplished major achievements during his reign. This article will cover the history of Constantine.
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Constantine was born in the city of Naissus in the Balkans in the year 272 CE. His father was Flavius Constantius, a Roman officer who quickly rose through the ranks to a prestigious position of glory. During this period, the Crisis of the Third Century, the Roman Empire was split into civil war. The crisis finally ended in the 280s, when Emperor Diocletian implemented reforms which split the empire into two allied emperors. In 293, Diocletian deepened these reforms by founding the Tetrarchy: a system where the two co-emperors of would share power with their successors.
Following the implementation of the Tetrarchy, Constantius was appointed the successor to one of the co-emperors, Maximian. As a result, his son Constantine received a full and privileged education. Notably, he watched on the sidelines as Emperor Diocletian brutally persecuted Christians in the empire. Growing weak in his old age, Emperor Diocletian resigned his office, driving Maximian to resign too. While Constantius rose to power as co-emperor, Diocletian refused to give Constantine the position of successor, instead pointing a different man to that position. Fleeing from threats to his life, Constantine reached his father Constantius, who was fighting a war in England. However, Constantius became weak during this campaign and soon died. Pressing his claim, Constantine declared himself the successor to his father. The other rulers negotiated; Constantine agreed to only have dominion over Spain, France, and England.
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As ruler of these regions, Constantine defeated enemy forces in battle and expanded cities. He was, nevertheless, still a junior member of the Tetrarchy. Meanwhile, the son of the old emperor Maximian, Maxentius, stewed in envy. In 306, Maxentius rose up in revolt and declared himself emperor, seizing control of Italy. Finally, Constantine marched against Maxentius in 312. They met in the Battle of Milvian Bridge.
As Constantine would later recount, some divine force told him to put the symbols Chi Rho, the first two letters of Christ, on the shields of his men before battle. Alternatively, some legends state that Constantine saw a cross in the heavens alongside the words "in hoc signo vinces," meaning "in this sign you will conquer." These events likely did not happen, but were rather later fabrications intended to legitimize the decision by Constantine to convert to Christianity. Despite being outnumbered, Constantine and his forces successfully defeated Maxentius, killing the would-be emperor.
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Soon, Constantine controlled Rome. As emperor, Constantine brutally eliminated the other threats to his power. He defeated his co-emperor in battle and eventually became the sole ruler of Rome in 326. As emperor, Constantine made major reforms to the government. For one, he diverged from his predecessors by repowering the Roman nobility in matters of government. While Constantine destroyed the Tetrarchy established by Diocletian, he continued other reforms, such as healing the inflationary system of Rome by formalizing the minting of gold coins; Diocletian had earlier attempted this. Like Diocletian, Constantine also waged war against the border enemies of Rome, conquering new lands.
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What good things did Constantine do? Chiefly, Constantine ceased the persecution of the large Christian population of Rome. Emperors like Diocletian and others had abused Christians, viewing them with suspicion, as they refused to worship the emperors as gods. In 313, Constantine and his co-emperor agreed to issue the Edict of Milan: this returned stolen churches to Christians and ceased persecution of that religion.
Perhaps the most important legacy of Constantine, however, was his conversion to Christianity. As emperor, Constantine sponsored Christian institutions throughout the Roman empire. He personally funded churches in Rome, for example. While Constantine sponsored Christianity, he also continued Roman Pagan institutions; for example, he minted coins bearing the image of the sun god Sol Invictus. For this reason, it is clear that Constantine favored pragmatism over religious absolutism.
In 325, Constantine convened the Council of Nicaea: a gathering of the leading Christian theologians whose purpose was to unite doctrine and reach a consensus. This council declared that Jesus Christ, God the Son, was the co-equal with God the Father. Religious disputes continued in Christianity, however.
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Despite spending years seizing power in Rome, Constantine saw that the old capital of the empire was strategically deficient, especially because of its distance from the frontier. Instead, Constantine established his base of operations in the city of Byzantium, which he renamed Constantinople in 324. Over the years, Constantine expanded and developed his new Rome. This city would go on to be the capital of the eastern Roman empire for more than a thousand years. Today, the city is now called Istanbul and is a key city in Turkey.
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Constantine the Great was a Roman emperor who ruled from 306 until 337. During his youth, Emperor Diocletian created the Tetrarchy: a system of power sharing featuring two main co-emperors and their two successors. Constantius, his father, was one of those co-emperors. After the death of his father, Constantine campaigned against his rivals for many years, finally securing sole power after defeating his enemies in battle.
As emperor, Constantine made several key reforms. He built upon the reforms of Diocletian by stabilizing inflation and minting gold coins. Constantine also established his base of operations not in Rome but Constantinople, the renamed and redeveloped ancient city of Byzantium. This city is now known as Istanbul. Constantine also enacted toleration for Christianity in the Edict of Milan, as well as converting to and sponsoring the religion himself. He gathered the Council of Nicaea to settle religious disputes. While a Christian, Constantine continued minting coins featuring the image of the sun god Sol Invictus; this suggests he was more pragmatic than dogmatic.
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Additional Info
Constantine the Great
The Roman Empire was great by many measures. After all, it ruled for roughly one thousand years. One of the most well-known emperors was Constantine I, known also as Constantine the Great. Why did later writers give him this title? His greatness rests on three pillars: his support of Christianity, his creation of the city of Constantinople, and his continuation of Diocletian's reforms in the Roman Empire.
In hoc signo vinces - Constantine and Christianity
No doubt many western historians bestow 'greatness' on Constantine because he actively supported Christianity, even though he may have not been a true convert until his death. His 'conversion' - historians debate the sincerity of this - came before he battled a fellow Roman ruler for power, Maxentius, at the Battle of the Milvian Bridge in 312 CE. According to Eusebius of Caesarea, a bishop and biographer of Constantine, the future emperor claimed he witnessed a cross in the sky with the words in hoc signo vinces, meaning 'By this conquer,' next to it. Constantine won the battle. The following year, he and another Roman ruler, Licinius, composed the Edict of Milan, which allowed for religious toleration in the Roman Empire: ''...that we might grant to the Christians and others full authority to observe that religion which each preferred''. With this, they legalized Christianity, which had been subject to occasional persecutions in the Empire.
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In 325, Constantine called and presided over the Council of Nicaea, which would prove monumental in the history of the faith. Here, several Christian officials debated the divine status of Jesus. They settled on what would become the basis of Christian teaching about Jesus' divinity, the Trinity.
Constantine waited until he was on his deathbed to receive baptism into the faith. While a common practice at the time, this act has surely led some scholars to question his sincerity towards Christian belief. Also problematic is the fact that even after legalizing Christianity, he still allowed coins to refer to Sol Invictus, or the 'Unconquerable Sun.' Constantine also appeared as a sun-god in statue form in another great achievement of his, the city of Constantinople. At least one scholar, Peter Sarris, writes that Constantine actually favored Christianity more once he settled his power in the eastern part of the Empire. Whether or not he personally believed in Christian doctrine throughout his life, Constantine no doubt actively supported the faith.
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'New Rome' at Constantinople
A second basis for Constantine's 'greatness' comes from his creation of a city that bore his name. Constantinople, now know as Istanbul in Turkey, was Constantine's attempt to create a 'New Rome' in the eastern Roman Empire. He built on an existing Greek city called Byzantion, which would later be used to name the Byzantine Empire. It was situated on the Bosporus Strait, which kept it safe from invaders until 1453 when it fell to the Ottoman Turks. Furthermore, in the fourth century, the eastern Empire was more wealthy, and Constantinople was a strong economic city. Under Constantine's rule, there was much construction in the city, including a palace for the residence of the emperor, and even a hippodrome for chariot races. In his attempt to create a 'New Rome,' Constantine created a whole city stamped by his ego.
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Maintaining an Empire
These two pillars, great as they are, also block out some of some more minor, but still important, accomplishments of keeping the Roman Empire together. Constantine continued the work of Diocletian, who divided up the Roman Empire into four 'tetrarchies' in the fourth century CE in order to more efficiently govern and defend it. Indeed, Constantine continued some of these reforms, such as keeping the borders safe and changes to Roman coinage. Constantine, it should be noted, went beyond Diocletian concerning leadership. He tried to consolidate more power under a hereditary form of rule after his death, which ultimately did not work. His sons fought one another, with Constantius II winning this fraternal fighting.
Lesson Summary
Constantine's greatness lay in his support of Christianity, his construction of Constantinople, and trying to keep the Roman Empire intact. Indeed, this was probably a main driving force behind many of his actions: to keep the Roman Empire together, which did at least, for a time, help out, as noted by scholars Jo Moran Cruz and Richard Gerberding. Constantine, one can imagine, saw himself as truly great even before writers crowned him with such greatness.
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Constantine the Great | Biography, History & Accomplishments
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