The Imperial German Navy or the Kaiserliche Marine was the navy of the German Empire, which existed between 1871 and 1919. It grew out of the small Prussian Navy, which was mainly for coast defence. Kaiser Wilhelm II greatly expanded the navy. The key leader was Admiral Alfred von Tirpitz, who greatly expanded the size and quality of the navy, while adopting the sea power theories of American strategist Alfred Thayer Mahan. The result was a naval arms race with Britain, as the German navy grew to become one of the greatest maritime forces in the world, second only to the Royal Navy.

Alfred Thayer Mahan was a United States naval officer and historian, whom John Keegan called "the most important American strategist of the nineteenth century." His book The Influence of Sea Power Upon History, 1660–1783 (1890) won immediate recognition, especially in Europe, and with its successor, The Influence of Sea Power Upon the French Revolution and Empire, 1793–1812 (1892), made him world-famous.