query: When was Constantine I born?
passage: Constantine the Great
Constantine the Great (Latin: Flavius Valerius Aurelius Constantinus Augustus; Greek: Κωνσταντῖνος ὁ Μέγας; 27 February c. 272 AD[1] – 22 May 337 AD), also known as Constantine I, was a Roman Emperor who ruled between 306 and 337 AD. Born on the territory now known as Niš (Serbian Cyrillic: Ниш, located in Serbia), he was the son of Flavius Valerius Constantius, a Roman Army officer. His mother was Empress Helena. His father became Caesar, the deputy emperor in the west, in 293AD. Constantine was sent east, where he rose through the ranks to become a military tribune under Emperors Diocletian and Galerius. In 305, Constantius was raised to the rank of Augustus, senior western emperor, and Constantine was recalled west to campaign under his father in Britannia (Britain). Constantine was acclaimed as emperor by the army at Eboracum (modern-day York) after his father's death in 306 AD. He emerged victorious in a series of civil wars against Emperors Maxentius and Licinius to become sole ruler of both west and east by 324AD.
passage: Constans
On 25 December 333, Constantine I elevated Constans to the rank of "Caesar" at Constantinople. Constans became engaged to Olympias, the daughter of the Praetorian Prefect Ablabius, but the marriage never came to pass. With Constantine’s death in 337, Constans and his two brothers, Constantine II and Constantius II, divided the Roman world among themselves and disposed of virtually all relatives who could possibly have a claim to the throne. The army proclaimed them "Augusti" on September 9, 337. Almost immediately, Constans was required to deal with a Sarmatian invasion in late 337, in which he won a resounding victory.
Constans was initially under the guardianship of Constantine II. The original settlement assigned Constans the praetorian prefectures of Italy and Africa. Constans was unhappy with this division, so the brothers met at Viminacium in 338 to revise the boundaries. Constans managed to extract the prefecture of Illyricum and the diocese of Thrace, provinces that were originally to be ruled by his cousin Dalmatius, as per Constantine I’s proposed division after his death. Constantine II soon complained that he had not received the amount of territory that was his due as the eldest son.