With the Type 89 I-Go fast becoming obsolete in the late 1930s, the Imperial Japanese Army (IJA) began a program to develop a replacement tank for infantry support. Experience during the invasion of Manchuria determined that the Type 89 was too slow to keep up with motorized infantry. The new medium tank was intended to be a scaled-up four-man version of the Type 95 Ha-Go light tank, although with a two-man turret, thicker armor, and more power to maintain performance.