On this day, December 2nd, 1804, Napoleon used a sacred ceremony to legitimize his reign as the absolute ruler of France. World History has the skinny: The Coronation of Napoleon I as Emperor of the French took place on Sunday 2 December 1804, in the Notre-Dame de Paris cathedral. A sacred ceremony held to legitimize Napoleon's reign, the coronation signaled the birth of the First French Empire (1804-1814; 1815) and established the imperial Bonaparte Dynasty. Significantly, the coronation was done in the presence of Pope Pius VII (served 1800-1823); along with the Concordat of 1801, this marked the reconciliation between France and the Catholic Church.