The Franco-Prussian War ended with French defeat. The Prussians included the occupation of Paris in the peace terms. The city and its National Guard had withstood the Prussian troops for six months. The population of Paris was defiant in the face of occupation—they limited the Prussian presence to a small area of the city and policed the 'boundary'. The French government of the Third Republic, headed by Louis-Adolphe Thiers, was concerned that the workers would arm themselves from the National Guard weapons and provoke the Prussians, so on March 18 French troops entered Paris to seize arms within the city. The National Guard refused to give up the weapons and the French government fled from the city to Versailles and declared war on Paris.
On March 26, a new municipal council of 81 was elected with Louis-Auguste Blanqui as president, and the Paris Commune was proclaimed on the 28th, although local districts often retained the organizations from the siege. They ended conscription and replaced the standing army with a National Guard of all citizens who could bear arms. The Commune also put a moratorium on unpaid war-time rents and stopped pawnshops from selling goods, as they were concerned that skilled workers had been forced to pawn their tools during the war. They separated the church from the state and made all church property state property, excluded religion from schools, postponed debt obligations, and abolished interest on the debts.
The Commune was assaulted from April 2 by the government forces of the Versailles Army, and the city was constantly bombarded. All captured Communards were shot, against what is now known as the Communards' Wall in the Père Lachaise cemetery. The government advantage was such that from mid-April on they refused to negotiate. The city wall was reached and breached in the west by May 21. The toughest resistance came in the more working-class districts of the east, where fighting continued for a further eight days of vicious street fighting (La Semaine Sanglante, the bloody week), before the final defeats in Belleville and Menilmontant. The government troops were culpable in the slaughter of unarmed citizens. Thirty thousand are believed to have died. Of the more than 30 000 more who were arrested, many were shot and 7 000 were exiled to New Caledonia. Few Communards escaped, mainly through the Prussian lines to the north. Government losses were around nine hundred. Paris remained under martial law for five years.
The commune adopted the previously discarded French Revolutionary Calendar during its brief existence.