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Who was Bishop Ambrose of Milan?

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Theodosius I Theodosius I, portrait on a gold coin from Mediolanum, Italy 378–383.

St. Ambrose (c. 339–397 CE) was the bishop of Milan, a prominent biblical critic, and a significant figure in early Christianity who was later declared a doctor of the church.12

Originally a Roman provincial governor, he was unexpectedly acclaimed as bishop by the people of Milan in 374. As bishop, he became a powerful cultural and political force, known for his eloquence and his role in converting and baptizing St. Augustine of Hippo.2

Ambrose is particularly noted for his complex relationship with the emperor Theodosius I. While he sought to cooperate with the emperor, he was a staunch defender of the church's moral authority. He famously rebuked Theodosius for his policies and, in 390, successfully compelled the emperor to perform public penance following a massacre in Thessalonica. Through his writings and actions, Ambrose established a model for medieval church-state relations, viewing the Christian emperor as a "dutiful son of the church" subject to its spiritual guidance.23