The purpose of this article is to investigate the intersection of the discourse of slavery - or doulology - and Romanness in Salvian of Marseilles' De gubernatione Dei. After providing a short overview of the author and his work, the study examines how Salvian considers the slavery to God as the most important expression of true Christian-Roman pietas. Thereafter Salvian's vice list, which is based on servile vices or uitia seruorum - including robbery, lying, greed, homicide, and sexual misconduct - is investigated to show how his Christian opponents fail both at being good masters of slaves and good slaves of God. The sexual abuse of slaves by Christian masters receives special attention. Finally, the study delineates the key dynamics and implications of Salvian's doulology, and shows that the Christian failure of mastery, both of the self and others, is what informs Salvian's view of why the Christian-Roman Empire is disintegrating under barbarian powers. The purpose of this article is to investigate the intersection of the discourse of slavery - or doulology - and Romanness in Salvian of Marseilles' De gubernatione Dei. After providing a short overview of the author and his work, the study examines how Salvian considers the slavery to God as the most important expression of true Christian-Roman pietas. Thereafter Salvian's vice list, which is based on servile vices or uitia seruorum - including robbery, lying, greed, homicide, and sexual misconduct - is investigated to show how his Christian opponents fail both at being good masters of slaves and good slaves of God. The sexual abuse of slaves by Christian masters receives special attention. Finally, the study delineates the key dynamics and implications of Salvian's doulology, and shows that the Christian failure of mastery, both of the self and others, is what informs Salvian's view of why the Christian-Roman Empire is disintegrating under barbarian powers.