The class was the last class of battlecruisers to be built by Germany in World War I. The design initially called for seven ships, but three of them were redesigned as the . Of the four ships of the class, , , and were launched, and was not—but none were completed, after wartime shipbuilding priorities were redirected towards U-boats—and the ships were broken up in the early 1920s. The lead ship of the class was named for August von Mackensen, a prominent military commander during the war. In response to the -class ships, the British Royal Navy laid down the s, all but one of which would eventually be cancelled; the sole survivor, , was completed after the end of the war. The design of the s was a much improved version of the previous . The most significant improvement was a new, more powerful gun, compared to the gun of the earlier ships. The -class ships also featured more powerful engines that gave the ships a higher top speed and a significantly greater cruising range. The design provided the basis for the subsequent class, armed with main-battery guns, after the Battle of Jutland in 1916 made the need for the larger guns clear. Design The fourth and final Naval Law, passed in 1912, governed the building program of the German navy during World War I. The Imperial Naval Office () decided the Navy should construct one battleship and one battlecruiser every year between 1913 and 1917, with an additional unit of both types in 1913 and 1916. Design work on the new class began in 1912, with construction intended to begin in the 1914 budget year. The question about the main battery for the new battlecruisers was the most pressing; the previous was armed with guns, though some consideration had been given to redesigning the last two ships— and —with guns. The 35 cm guns were heavier than the 30.5 cm guns, and there were problems with enlarging the new ships to accommodate the heavier armament. The Imperial dry docks were deep enough only for ships with a draft of , and simply accepting an increased displacement on the same hull as the class would entail a reduction in speed. This meant that an increase in displacement would necessitate a longer and wider hull to keep any increases in draft minimal and avoid reducing the speed. The constraints on