A highly educated imperial official of northern Italy, Ambrose famously received baptism shortly before his consecration as Bishop of Milan in 373. This collection of translated letters has been arranged in categories according to the recipients: to emperors, to bishops, to priests, to his sister (a consecrated virgin), and to laymen, in addition to synodal letters. Two of his letters to his sister, Marcellina, are a useful source for examining Ambrose's management of church-state relations.