Answer
Licinius was executed on Constantine I's orders after the Battle of Chrysopolis. The battle was fought on September 18, 324, near Chrysopolis (now Üsküdar, Turkey), and was the final battle in the civil war between Licinius and Constantine I. Constantine's victory at Chrysopolis resulted in the unification of the Roman Empire under his rule. Licinius was captured and executed on Constantine's orders shortly after the battle.