In 1938, the Imperial Japanese Army introduced the Type 97 Chi-Ha as its new medium tank, drawing on lessons from earlier models. Its 170 hp Mitsubishi air-cooled diesel engine gave it decent mobility for the era, while the six-wheel leaf-spring suspension—adapted from the Type 95 Ha-Go light tank—helped it traverse rough terrain in Manchuria and China. Armed with a 57 mm infantry-support gun inherited from the Type 89 I-Go, the Chi-Ha excelled in infantry-tank cooperation during the Second Sino-Japanese War, its low silhouette and distinctive semicircular radio antenna marking it out on the battlefield. Though adequate against lightly armoured foes, its gun struggled against better-protected Soviet tanks at Khalkhin Gol in 1939, exposing its need for greater firepower. As World War II spread across the Pacific, the Chi-Ha remained Japan’s most numerous medium tank but lagged behind Allied counterparts in armour and armament. Encounters in New Guinea and the Philippines revealed its vulnerabilities, as its 57 mm gun could not penetrate thicker Allied armour, and its thin plating left crews exposed to return fire. In 1942, engineers addressed these flaws by fitting a larger three-man turret and the new Type 1 47 mm high-velocity gun, creating the Type 97 Shinhōtō Chi-Ha (‘new turret’). Though still outmatched by late-war Allied tanks, this improved variant restored some battlefield relevance, illustrating Japan’s ongoing efforts to modernize under the pressures of a rapidly evolving armoured war.