Constantin Ier

Proclaimed at York in 306 at the death of his father Constantius, Constantine conquered the empire piece by piece over eighteen years, then governed it alone for thirteen. Two decisions changed history: the turn to Christianity after the victory at the Milvian Bridge, and the founding of Constantinople, the new Rome. He also created the gold solidus, a stable coin for seven centuries, and died in 337, baptised on his deathbed.

This coin dates from the standoff with Licinius: an empire split between two Augusti, imperial vows displayed on the reverses, and massive issues for the armies until the final victory of 324.