October 28, AD 312 ~ Constantine defeats Maxentius at the Battle of the Milvian Bridge

Detail from Romano's Battle of the Milvian Bridge, showing Constantine,
on horseback, victorious over Maxentius who is shown drowning in the
Tiber River, lower right. (Click to enlarge)

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October 28 marks the anniversary of the Battle of the Milvian Bridge (AD 312) at which Constantine the Great defeated the usurper Maxentius who had set himself up as emperor in Rome. Son of the emperor Maximian Herculius, Maxentius claimed the same right to the throne that Constantine had claimed from his own father, the emperor Constantius I Chlorus. The difference was that Constantius conferred the imperial power upon his son Constantine on his deathbed, whereas Maxentius took his father's authority by force and drove the old man from Rome.

After two failed attempts by Severus and Galerius to end the usurpation of Maxentius by military force, it was left to Constantine to settle the affair from his base in Gaul. 

I wrote a more detailed and updated account of the battle and Lactantius's account of it here:

“Constantine can not be overcome!” ~ Constantine enters Rome in triumph after the Battle of the Milvian Bridge, October 28, AD 312 

Other articles pertaining to this period may be found at the following links:

• Constantine's Vision of the Cross ~ Early Accounts and Backstory
• "He bade the lapsed weep for their crimes" ~ The ancient sources for Pope Saint Marcellus who died AD 309
• Constantine — Military Hero and Christian Emperor
• Constantine's Execution of Crispus and Fausta
• September 18, AD 324 -- Constantine defeats Licinius at the Battle of Chrysopolis
• Death of Constantius I, the father of Constantine the Great ~ Primary Accounts