Constantius II ruled the Roman Empire between 337-361 CE. He was the second son of Constantine the Great and Fausta. Constantius was a devout follower of Arianism Christianity. Ruling for 24 years, he was the longest reigning son of Constantine and therefore, arguably, the most successful.
This is a companion discussion topic for the original content at https://www.worldhistory.org/Constantius_II/.