Mos maiorum

The mos maiorum ("ancestral custom" or "way of the elders," plural mores, with maiorum a genitive plural; cf. English "mores") is the unwritten code from which the ancient Romans derived their social norms. It is the core concept of Roman traditionalism, distinguished from but in dynamic complement to written law. The mos maiorum was collectively the time-honoured principles, behavioural models, and social practices that affected private, political, and military life in ancient Rome.

The Roman family (the familia, better translated as "household" than "family") was hierarchical, as was Roman society. These hierarchies were traditional and self-perpetuating, that is, they supported and were supported by the mos maiorum. The pater familias, or head of household, held absolute authority over his familia, which was both an autonomous unit within society and a model for the social order, but he was expected to exercise this power with moderation and to act responsibly on behalf of his family. The risk and pressure of social censure if he failed to live up to expectations was also a form of mos.

The distinctive social relationship of ancient Rome was that between patron (patronus) and client (cliens). Although the obligations of this relationship were mutual, they were also hierarchical. The relationship was not a unit, but a network (clientela), as a patronus might himself be obligated to someone of higher status or greater power, and a cliens might have more than one patron, whose interests might come into conflict. If the familia was the discrete unit underlying society, these interlocking networks countered that autonomy and created the bonds that made a complex society possible. Although one of the major spheres of activity within patron-client relations was the law courts, patronage was not itself a legal contract; the pressures to uphold one's obligations were moral, founded on the quality of fides, "trust" (see Values below), and the mos. Patronage served as a model when conquerors or governors abroad established personal ties as patron to whole communities, ties which then might be perpetuated as a family obligation. In this sense, mos becomes less a matter of unchanging tradition than precedent.

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