Question: What helmet typically associated with the Prussian Army was replaced by a steel helmet during World War I?
Sentence (from "Pickelhaube"): The Pickelhaube (plural "Pickelhauben"; from the German "Pickel", "point" or "pickaxe", and "Haube", "bonnet", a general word for "headgear"), also Pickelhelm, was a spiked helmet worn in the nineteenth and twentieth centuries by German military, firefighters, and police.
Relevant evidence: Yes