To meet government orders, production in World War I increases to more than five-fold its pre-war level. Particularly well known is the heavy 42 cm mortar "Big Bertha". Krupp invests most of the profits made at the beginning of the war in sophisticated new factories for which the company later has no use.
The initially high reserves are eroded by soaring personnel and social costs during and after the war and by the necessary production changes.
