The Siegfried class was a group of six coastal defense ships built by the German Kaiserliche Marine ("Imperial Navy") in the late 19th century. The ships were intended to protect the German coastline from naval attacks. The class comprised the lead ship Siegfried, along with her sisters Beowulf, Frithjof, Heimdall, Hildebrand, and Hagen. All six ships were named after Norse mythological figures. Two further vessels, the Odin class, were built to a similar design but were not identical.
The Siegfried-class ships were obsolete by the outbreak of World War I, and saw only limited service in their intended role before they were withdrawn from active duty. The ships then served in a variety of secondary duties, including barracks ships, target ships, and in the case of Beowulf, an icebreaker in the Baltic Sea. All six ships were struck from the naval register on 17 June 1919, days before the Treaty of Versailles was signed. Five of the ships were sold for scrapping immediately after they were struck from the register (with Hildebrand being lost in transit), but Frithjof was purchased by a shipping company, and converted into a freighter. She served in this capacity until she too was scrapped in 1930.
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