Douaumont, the keystone of the system of forts that was to protect Verdun against a German invasion, had been given up without a fight. In the words of one French divisional commander, its loss would cost the French army 100,000 lives. Douaumont's easy fall was a disaster for the French and a glaring example of the lack of judgment prevailing in the General Staff at the time, under General Joffre. The French General Staff had decided in August 1915 to partially disarm all the Verdun forts, acting under the erroneous assumption that the forts could not resist the effects of modern heavy artillery. After its capture, Douaumont became an invulnerable shelter and operational base for German forces just behind their front line. The German soldiers at Verdun came to refer to the place as "Old Uncle Douaumont".