Saint Ambrose became archbishop of Milan in 374 and later baptized Saint Augustine.
Ambrose was born around 340 in Trier and trained for a career in Roman government. While serving as governor in northern Italy, he was unexpectedly chosen bishop of Milan in 374, even though he was not yet baptized. He was baptized, ordained, and consecrated within a short period.
As bishop, Ambrose became an influential theologian, preacher, and church leader. He opposed Arian theology and famously challenged Emperor Theodosius I after the massacre at Thessalonica, requiring public penance before readmitting him to communion.
Ambrose also influenced Augustine, who listened to his preaching in Milan. Ambrose baptized Augustine and several others at Easter in 387. The two men are sometimes confused in questions about Augustine’s conversion: Monica was Augustine’s mother, while Ambrose was the bishop who baptized him.