L 20e α was a design for a class of battleships to be built in 1918 for the German Kaiserliche Marine during World War I. Design work on the class of battleship to succeed the Bayern-class battleships began in 1914, but the outbreak of World War I in July 1914 led to these plans being shelved. Work resumed in early 1916 and lessons from the Battle of Jutland, fought later that year, were incorporated into the design. Reinhard Scheer, the commander of the fleet, wanted larger main guns and a higher top speed than earlier vessels, to combat the latest ships in the British Royal Navy. A variety of proposals were submitted, with armament ranging from the same eight 38 cm (15 in) guns of the Bayern class to eight 42 cm (16.5 in) guns.

The Bayern class was a class of four super-dreadnought battleships built by the German Kaiserliche Marine. The class comprised Bayern, Baden, Sachsen, and Württemberg. Construction started on the ships shortly before World War I; Baden was laid down in 1913, Bayern and Sachsen followed in 1914, and Württemberg, the final ship, was laid down in 1915. Only Baden and Bayern were completed, due to shipbuilding priorities changing as the war dragged on. It was determined that U-boats were more valuable to the war effort, and so work on new battleships was slowed and ultimately stopped altogether. As a result, Bayern and Baden were the last German battleships completed by the Kaiserliche Marine.