Constantine the Great: Accomplishments & Quotes

Instructor: Joshua Riddle

Joshua teaches pre-modern World History and has a Master of Arts degree in History.

Constantine I is one of the more well-known emperors in the history of the Roman Empire. During his reign, he accomplished many things. In this lesson, we will learn about these accomplishments, including his legalization of Christianity, his founding of Constantinople, and his reforms of Diocletian to keep the Roman Empire together.

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.

Giulio Romano, The Battle of Milvian Bridge, 1520-1524

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.

Peter Paul Reubens, designer, Tapestry Showing Constantine Directing the Building of Constantinople, 1623-1625

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