SMS Pillau was a light cruiser of the Imperial German Navy. The ship, originally ordered in 1913 by the Russian navy under the name Maraviev Amurskyy, was launched in April 1914 at the Schichau-Werke shipyard in Danzig. However, due to the outbreak of World War I in August 1914, the incomplete ship was confiscated by Germany and renamed SMS Pillau for the East Prussian port of Pillau. Pillau was commissioned into the German Navy in December 1914. She was armed with a main battery of eight 15 cm SK L/45 (5.9-inch) guns and had a top speed of 27.5 kn. One sister ship was built, Elbing.

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.