Authored By Dan Alex (Updated: 7/1/2014):
After World War 1, the light tank proved all the rage to discerning budget-minded military customers of the world. As such, Fiat-Ansaldo took to designing a new light tank based on its successful Carro Armato L3 "tankette" for the purpose of export. The L3 was developed during the early part of the 1930s - itself being heavily influenced by the successful British-designed Carden Lloyd Mark VI Tankette- and began serial production in 1935, running to 1938 with as many as 2,500 examples ultimately delivered. The type went on to see action almost immediately and throughout a variety of conflicts waged across Europe including the Spanish Civil War - what essentially proved to be an active test ground for the Axis prior to World War 2. The L3 was in service up to about 1944 when it was clear that the tankette was outmatched by most every other tank being fielded and that stage of the war - essentially bringing an end to the age of the tankette in whole. Regardless, the widespread use and proven qualities of the vehicle made it a sensible notion to produce an offshoot based on the type.
As such, several prototypes soon emerged. An early form mounted a 37mm main gun in a side sponson with a traversing main turret housing 2 x 8mm Breda machine guns. Another form then saw the 37mm main gun set within the turret installation along with a single 8mm coaxial machine gun. Still another design initiative did away with cannon armament altogether and fitted 2 x 8mm machine guns in the turret. By 1939, the design was finalized with a 20mm Breda Model 35 series main gun and a coaxially-mounted 8mm Breda Model 38 series machine gun - both to be held in a traversing turret. The tank would be crewed by two personnel made up of the driver and the commander. Unfortunately for the commander, he would also have to double as the gunner (of both weapons) and loader. When Italian authorities came across this new design, interest was such that the type was formally accepted into Italian Army service as the "L6/40". L6/40s were delivered to awaiting Italian cavalry and reconnaissance elements.
Of note here is that the Italian Army utilized a unique, sometimes confusing, identification system for their tanks. In the case of the "L6/40", the designation actually breaks down quite conveniently to clearly label various identifiable pieces. The "L" indicated "light" (or "Leggero" in Italian) to cover the light classification of the L6/40 series. The use of the number "6" detailed the vehicle's general operating weight while the "40" was nothing more than an identifier used to mark the vehicle's year of formal acceptance into service.