It was on this day in 312 that Constantine the Foul realized that if he deceived Christians into thinking he was one of them, they would fall into his lap like lapdogs because too many of them sought earthly power.
Naturally he continued to live the remainder of his life as a thoroughgoing pagan and only stooped to accept baptism on his death bed. But Christians then, as now, were unwilling or unable to see the truth: he had manipulated them and they were willing manipulants.
Constantine is the worst thing that ever happened to the Church. The. Worst. Thing. As von Harnack notes
The head of the Church is Christ, not the Pope; only through Constantine has the latter, as the bishop of Rome, become great.
Constantine. The. Foul.