Prince Shapur I becomes co-ruler of the Sasanian Empire with his father King Ardashir I. Maharaja Sri-Gupta becomes ruler of the Gupta Empire (approximate date). Mani, a young mystic of Ctesiphon, proclaims himself a prophet at the court of Ardashir I. He preaches his doctrine, Manichaeism, throughout the Sassanid Empire.
The Roman Empire is threatened on several fronts at the same time. Africa revolts and tribes in northwest Germania, under the name of the Franks, are raiding the Rhine frontier.source
Siege of Hatra: The Sasanians besiege the capital of the Kingdom of Hatra ruled by Sanatruq II.source
Mani, a young mystic of Ctesiphon, proclaims himself a prophet at the court of Ardashir I. He preaches his doctrine, Manichaeism, throughout the Sassanid Empire.source