The Carro Armato M13/40 was a development of the M11/39 tank, the first experiment and breakthrough for Italian tank building. However, due to the unfortunate placement of the gun in the hull, the tank's crew could not fully utilise its already not particularly large potential. Furthermore, the gunner was overloaded with duties, as besides aiming the gun, he also had to load it. Taking these shortcomings into account, the Italian army put forward requirements for improving the M11/39 tank.

Thus, the new tank was requested to feature a full turret with a more powerful 47 mm gun, and the crew was expanded to four people by adding a loader. Over time, it became clear that to install a turret with a full-fledged gun, the tank's hull would also need to be modernised. As a result, the Ansaldo firm prepared a project for a tank with a new hull and turret, but using the old running gear. The first prototype was trialled in 1938, and in 1940 the tank was adopted by the Italian army under the designation M13/40. 100 tanks were built in the first production series, and improvements were subsequently made in the form of the M13/40 (II) and (III).

Introduced in Update 1.85 "Supersonic", the tank has satisfactory armour and a decent gun, but suffers from slow reload times and mediocre mobility. The M13/40 (I) is typically used as a breakthrough tank due to the fact that it is very resistant to enemy fire especially when angled and can disable or destroy enemy vehicles with only one shot when up close. Beware, however, around the 500 m mark, the cannon ammunition starts to lose its punch and can fail to penetrate effectively.