Cardinal Richelieu, French cardinal and politician, Chief Minister to the French Monarch (b. 1585)

Armand Jean du Plessis, Duke of Richelieu (French: [aʁmɑ̃ ʒɑ̃ dy plɛsi]; 9 September 1585 – 4 December 1642), known as Cardinal Richelieu, was a French clergyman and statesman. He was also known as l'Éminence rouge, or "the Red Eminence", a term derived from the title "Eminence" applied to cardinals, and the red robes they customarily wore.

Consecrated as a bishop in 1607, he was appointed Foreign Secretary in 1616. He continued to rise in both the Catholic Church and French government, becoming a cardinal in 1622, and Chief minister to Louis XIII of France in 1624. He retained this office until his death in 1642, when he was succeeded by Cardinal Mazarin, whose career he had fostered.

Richelieu sought to consolidate royal power and by restraining the power of the nobility, he transformed France into a strong, centralized state. In foreign policy, his primary objective was to check the power of the Habsburg dynasty in Spain and Austria, and ensure French dominance in the Thirty Years' War that engulfed Europe. Despite suppressing French Protestants, he made alliances with Protestant states like the Kingdom of England and the Dutch Republic to achieve his goals. Though he was a powerful political figure, events such as the Day of the Dupes, or Journée des Dupes, show this power was still dependent on the king's confidence.

An alumnus of the University of Paris and headmaster of the College of Sorbonne, he renovated and extended the institution. He was famous for his patronage of the arts, and founded the Académie Française, the learned society responsible for matters pertaining to the French language. As an advocate for Samuel de Champlain and New France, he founded the Compagnie des Cent-Associés; he also negotiated the 1632 Treaty of Saint-Germain-en-Laye, under which Quebec City returned to French rule after its loss in 1629.

Richelieu has frequently been depicted in popular fiction, principally as the lead villain in Alexandre Dumas's 1844 novel The Three Musketeers and its numerous film adaptations.