In 1798, Lucien was elected member of the Council of Five Hundred for Corsica's Liamone department. Later, as president of the Council, which he moved to the suburban security of Saint-Cloud – Lucien Bonaparte was crucial with a combination of bravado and disinformation to the coup d'état of 18 Brumaire (date based on the French Republican Calendar) in which Napoleon Bonaparte overthrew the government of the Directory to replace it by the Consulate on 9 November 1799. Lucien mounted a horse and galvanized the grenadiers by pointing a sword at his brother and swearing to run him through if he ever betrayed the principles of Liberté, égalité, fraternité. The following day Lucien arranged for Napoleon's formal election as First Consul.
