From the post:
In the 1920s and 1930s many European nations valued the idea of multi-turreted heavy breakthrough tanks, and the T-35 was the Soviet Union's take on this concept. Design work on the T-35 tank began in 1930. Two design teams worked on competing designs, but eventually the team working on a design similar to the British Vickers A1E1 Independent won out.
The first prototype was produced in July 1932, with a 76.2mm-armed central turret and four smaller turrets arranged around it. Two of the smaller turrets were armed with 37mm guns and co-axial machine-guns and two just with machine-guns. This prototype proved too complex for mass production, so work began on a simpler design.
The new design replaced the 37mm guns in the secondary turrets with more powerful 45mm guns, and the redesigned turrets were standardised with those used on the T-26 light tank and T-28 heavy tank with a few minor differences. The main turret was also fitted with a rear-facing slot that could be used to fire a machine-gun from.
On 11 August 1933, the modified T-35 design was accepted for production. Manufacturing began at the Kharkov Locomotive Factory and 20 vehicles were completed. A second batch of 35 T-35 obr 1935 tanks was completed in by 1938. Six of a final model (obr 1938) were produced in 1939 for a total of 61 T-35 tanks built overall.. These last tanks were fitted with new turrets made with sloped armour.
Most of the T-35 tanks were with the 5th Separate Heavy Tank Brigade stationed in Moscow, and its 50 T-35 tanks spent most of the pre-war period taking part in parades as a showpiece unit. In March 1940, the 5th Separate Heavy Tank Brigade with its T-35 tanks was renamed the 68th Tank Regiment and combined with the 14th Tank Brigade to form the 34th Tank Division. The division served with the 8th Mechanized Corps in the Kiev Special Military District.