Seydlitz, an Admiral Hipper-class cruiser, was built in Bremen. In June 1942, when the ship was 95% complete, the construction was halted—the Japanese attack on Pearl Harbor highlighted the need for aircraft-capable ships. The nearly completed cruiser was designated for conversion into an aircraft carrier and renamed Weser. The work commenced in December 1942 but ceased half a year later. The ship was then towed to Königsberg. Her hull was blown up in January 1945 as the Red Army was going to take the city.