Imperial cult (Roman Empire)

The Imperial cult of ancient Rome identified emperors and some members of their families with the divinely sanctioned authority (auctoritas) of the Roman State. Its framework was formulated during the early Principate of Augustus, and was rapidly established throughout the Empire and its provinces, with marked local variations in its reception and expression.

Augustus's reforms transformed Rome's Republican system of government to a de facto monarchy, couched in traditional Roman practices and Republican values. The princeps (later known as Emperor) was expected to balance the interests of the Roman military, Senate and people, and to maintain peace, security and prosperity throughout an ethnically diverse empire. The official offer of cultus to a living emperor acknowledged his office and rule as divinely approved and constitutional: his Principate should therefore demonstrate pious respect for traditional Republican deities and mores.

A deceased emperor held worthy of the honor could be voted a state divinity (divus, plural divi) by the Senate and elevated as such in an act of apotheosis. The granting of apotheosis served religious, political and moral judgment on Imperial rulers and allowed living Emperors to associate themselves with a well-regarded lineage of Imperial divi from which unpopular or unworthy predecessors were excluded. This proved a useful instrument to Vespasian in his establishment of the Flavian Imperial Dynasty following the death of Nero and civil war, and to Septimius in his consolidation of the Severan dynasty after the assassination of Commodus. In the development of Imperial rule from Principate to Dominate, the role of the Senate was increasingly marginalised and military loyalty became the key to Imperial authority.

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