U1431

U-1431 was a German submarine of the Kriegsmarine built during World War II. It belonged to the Type XXI U-boat class, a late-war design that emphasized submerged performance with a larger battery and a snorkel system. Type XXI boats were intended to operate primarily underwater and represent a turning point in submarine design, influencing future generations of submarines.

U-1431 was laid down in 1944 and launched in 1945 by a German shipyard. Due to the late stage of the war, the submarine conducted only a limited set of operations before surrendering to Allied forces in 1945. After the war, U-1431 was surrendered and subsequently broken up; no complete Type XXI submarine survives.

In historical references, U-1431 is cited as an example of the late-war U-boat program and the transition toward greater underwater capability. The class' technological features, particularly its increased submerged endurance and snorkel operation, influenced postwar submarine design.