Franco-Prussian War
During the fighting, the Communards killed c. 500 people, including the Archbishop of Paris, and burned down many government buildings, including the Tuileries Palace and the Hotel de Ville. Communards captured with weapons were routinely shot by the army and Government troops killed from 7,000–30,000 Communards in the fighting and in massacres of men, women, and children during and after the Commune. More recent histories, based on studies of the number buried in Paris cemeteries and in mass graves after the fall of the Commune, put the number killed at between 6,000 and 10,000. Twenty-six courts were established to try more than 40,000 people who had been arrested, which took until 1875 and imposed 95 death sentences, of which 23 were inflicted. Forced labour for life was imposed on 251 people, 1,160 people were transported to "a fortified place" and 3,417 people were transported. About 20,000 Communards were held in prison hulks until released in 1872 and a great many Communards fled abroad to England, Switzerland, Belgium or the United States. The survivors were amnestied by a bill introduced by Gambetta in 1880 and allowed to return.

Q: What famous palace was also burned down?
Tuileries Palace