Which was discussed in the prior comment. Louis Napoleon got man-handled and France was abke to but up only a token (albeit bloody) resistance against the combined German forces. The German Empire was declared in the Versailles Palace while Paris was under seige during the war. Honestly i would say it was an even more humiliating defeat for France than WW2. All your enemies uniting their countries into one on your own soil while the war is still ongoing is straight up disrespectful. It would be akin to the Potsdsmn conference being held on the deck of the USS Missouri in the middle of Tokyo Bay before the atomic bombings.