Le repentir est le dernier profit que l'homme tire de sa faute.
François de La Rochefoucauld
Sacre-Coeur was commissioned by the French National Assembly in 1873, following the tumultuous year of the Franco-Prussian War and the Paris Commune. It was in this period that France had suffered a humiliating military defeat, Emperor Napoleon III fled into exile, Paris itself had been under siege, and the riotous period of the Paris Commune that followed caused thousands of deaths and destroyed many buildings - including the Tuileries Palace and the Hotel de Ville. Sacre-Coeur was the initiative of Alexandre Legentil and Hubert Rohault de Fleury as the saw the defeat of France was a spiritual one. They vowed to build a church dedicated to the Sacred Heart “as reparation” (i.e. as penance for infidelity and sin) for they held that the misfortunes of France had spiritual rather than political causes.
In a still-controversial decision in 1873, the National Assembly voted to use the highest and most visible land in the city to "expiate the crimes of the Commune". The angry debate about the church was indicative of the schism in the French social order, with royalists and reactionary Catholics on one side, and democrats, socialists and rationalists on the other. The bishops of the Catholic Church supported the idea of course, but it was opposed by many others, including French president Georges Clemenceau. The work was funded from donations - in many cases modest - collected throughout France, the names of the donors being carved in the stone.
The first stone of the Sacré-Coeur, whose construction was laid on 16 June 1875. A stone extracted in Seine-et-Marne in the Château-Landon quarry, about 25 km south of Fontainebleau, which was used at the beginning of the 19th century for the construction of the Arc de Triomphe. Its characteristic ? This stone is self-cleaning. For the construction of the basilica was not chosen the limestone of Paris, extracted since Antiquity in a quarry of the Oise. The architect of the Sacré-Coeur preferred to call on the quarry of Souppes-sur-Loing, in Seine-et-Marne, and its “Château-Landon” stones. In contact with rainwater, the cullet, a thin protective layer that naturally coats the stone, secretes a white substance which hardens in the sun.
Even as the foundation stones were finally laid in 1875 ongoing political debates slowed progress. One fractious debate of 1880 called the basilica a provocation to civil war and proposed reversing the 1873 decree that granted the property rights for the church. In the end, at least five different architects were involved in completing the design; construction was not completed until 1914 - just in time for World War I. Sacre-Coeur took longer to complete than did the Parthenon in Athens.