Execution of King Louis XVI in the context of "Proclamation of the abolition of the monarchy"

The ancien régime (/ˌɒ̃sjæ̃ reɪˈʒiːm/; French: [ɑ̃sjɛ̃ ʁeʒim] ; lit. 'old rule') was the political and social system of the Kingdom of France that the French Revolution overturned through its abolition in 1790 of the feudal system of the French nobility and in 1792 through its execution of King Louis XVI and declaration of a republic. "Ancien régime" is now a common metaphor for "a system or mode no longer prevailing".

The administrative and social structures of the ancien régime in France evolved across years of state-building, legislative acts (like the Ordinance of Villers-Cotterêts), and internal conflicts. The attempts of the House of Valois to reform and re-establish control over the scattered political centres of the country were hindered by the Wars of Religion from 1562 to 1598. During the House of Bourbon, much of the reigns of Henry IV (r. 1589–1610) and Louis XIII (r. 1610–1643) and the early years of Louis XIV (r. 1643–1715) focused on administrative centralization. Despite the notion of "absolute monarchy" (typified by the king's right to issue orders through lettres de cachet) and efforts to create a centralized state, ancien régime France remained a country of systemic irregularities: administrative, legal, judicial, and ecclesiastic divisions and prerogatives frequently overlapped, the French nobility struggled to maintain their influence in local judiciary and state branches while the Fronde and other major internal conflicts violently contested additional centralization.