Roman Emperor Constantius II ruled from 337 to 361 AD, following the death of his father, Constantine the Great. He was the second son of Constantine and played a significant role in the division of the Roman Empire, governing the eastern provinces while his brothers managed the west. Constantius II is known for his strong support of Arianism, a Christian doctrine that opposed the Nicene Creed. His reign was marked by religious conflicts and military challenges, including battles against the Persian Empire and internal strife within the Roman Empire. He died in 361 AD while campaigning against the Persians.