High Quality Content by WIKIPEDIA articles! The German commerce raiders of World War I were those surface vessels used by the Imperial German Navy to pursue its war on Allied commerce, (the Handelskreig). These comprised regular warships, principally cruisers, stationed in Germany’s colonial empire, express liners commissioned as auxiliary cruisers and, later, freighters outfitted as merchant raiders. These vessels had a number of successes, and a significant impact on Allied naval strategy, particularly in the early months of the war.