Thepickelhaube was ahelmet used by theGerman army from the 19th century until theFirst World War (1914-1918). It was a helmet made of hardenedleather, which had a characteristic metalspike on its top, which is believed to be merelydecorative. The pickelhaube was designed in 1842 by KingFrederick William IV ofPrussia and its use slowly spread to other German states. In theFirst World War it was replaced by a steel helmet calledStahlhelm (German: "steel helmet"), which was used until theSecond World War, since the pickelhaube, being made of hardened leather, did not offer protection to the head of a soldier againstartilleryshrapnel, for example.