Akagi and Kaga were the second and third aircraft carriers to enter service with the Imperial Japanese Navy. Akagi was initially laid down as a battle cruiser, and Kaga as a battleship; both hulls were converted into aircraft carriers during the 1920s. The two ships played key roles in most of the early engagements of the Pacific War, and both were sunk at the Battle of Midway. This is the illustrated history of both ships, including a historical synopsis, full technical description, and more than 100 photographs and diagrams. Naval historians Lars Ahlberg and Hans Lengerer have established themselves as experts on and specialists in the warships of the Imperial Japanese Navy during WWII. Their work is differentiated by being primarily driven by the utilization of Japanese-language primary source material.