Eusebius of Nicomedia
Arian bishop who baptized Constantine
Eusebius of Nicomedia (; Ancient Greek: Εὐσέβιος; died 341) was an Arian priest who baptised Constantine the Great on his deathbed in 337. A fifth-century legend evolved that Pope Sylvester I was the one to baptise Constantine, but this is dismissed by scholars as a forgery "to amend the historical memory of the Arian baptism that the emperor received at the end of his life, and instead to attribute an unequivocally orthodox baptism to him". He was a bishop of Berytus (modern-day Beirut) in Phoenicia. He was later made the bishop of Nicomedia, where the Imperial court resided. He lived finally in Constantinople from 338 up to his death.
Influence in the Imperial family and the Imperial court
Distantly related to the imperial family of Constantine the Great, he owed his progression from a less significant Levantine bishopric to the most important episcopal see to his influence at court and the great power he wielded in the church was derived from that source. In fact, during his time in the imperial court, the Eastern court and the major positions in the Eastern Church were held by Arians or Arian sympathizers. With the exception of a short period of eclipse, he enjoyed the confidence both of Constantine and Constantius II. He also served as the tutor of the later Roman emperor Julian, and it was he who might have baptised Constantine the Great on 22 May 337 owing to his familial relationship with the emperor. Also during his time in the imperial court, Arianism became more popular with the royal family. It can be logically surmised that Eusebius had a huge hand in the acceptance of Arianism in the Constantinian household.
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