The German submarine U-155 on display in St. Katherine docks, London, England, December 1918. The SM U-155 (formerly merchant submarine “Deutschland”) was a Type U-151 U-Kreuzer of the Kaiserliche Marine during World War I. Built at Flensburger Schiffbau, she was launched on 28 March 1916 as merchant submarine “Deutschland” Deutschland was a blockade-breaking German merchant submarine used during World War I. It was developed with private funds and operated by the North German Lloyd Line. She was one of the first of seven U-151 class U-boats built and one of only two used as unarmed cargo submarines.