Constantine the Great was a conqueror at heart and began his adventures in battle. His men respected him like anyone with a touch of grace and charisma. To understand Constantine's influence on artists, one must learn about Constantine himself:
"He was born at Naissus, now Nisch in Servia Nis, Serbia --Ed., the son of a Roman officer, Constantius, who later became Roman Emperor, and St. Helena, a woman of humble extraction but remarkable character and unusual ability. The date of his birth is not certain, being given as early as 274 and as late as 288. After his father's elevation to the dignity of Caesar we find him at the court of Diocletian and later (305) fighting under Galerius on the Danube. When, on the resignation of his father, Constantius was made Augustus, the new Emperor of the West asked Galerius, the Eastern Emperor, to let Constantine, whom he had not seen for a long time, return to his father's court. This was reluctantly granted. Constantine joined his father, under whom he had just time to distinguish himself in Britain before death carried off Constantius (25 July, 306). Constantine was immediately proclaimed Caesar by his troops, and his title was acknowledged by Galerius somewhat hesitatingly. This event was the first break in Diocletian's scheme of a four-headed empire (tetrarchy) and was soon followed by the proclamation in Rome of Maxentius, the son of Maximian, a tyrant and profligate, as Caesar, October, 306. " (The Catholic Encyclopedia.)
At the time Constantine was emperor, (300 AD), he shared power with Maxentius from then until 312 AD. They split the empire in two with Constantine taking the Western section and Maxentius ruled the Eastern area. While Constantine the Great was out busy at war conquering land, Maxentius soon became jealous of his numerous achievements. Thus war between the two rulers became inevitable. The battle between both is known as the Battle of Mulvian Bridge which occurred in Italy around 312. The night...