The German navies—specifically the Kaiserliche Marine and Kriegsmarine of Imperial and Nazi Germany, respectively—built a series of battleships between the 1890s and 1940s. To defend its North and Baltic Sea coasts in wartime, Germany had previously built a series of smaller ironclad warships, including coastal defense ships, and armored frigates.[lower-alpha 1][1] With the accession to the throne of Kaiser Wilhelm II in 1888, the Kaiserliche Marine began a program of naval expansion befitting a Great Power.[2] The navy immediately pushed for the construction of the four Brandenburg-class battleships, after which soon followed five Kaiser Friedrich III-class ships.[3] The appointment of Admiral Alfred von Tirpitz to the post of State Secretary of the Navy in 1897 accelerated naval construction.