After Finland refused Soviet demands to cede territory, the brigade and its parent corps were committed to the invasion that began the Winter War.

Awarded the Order of the Red Banner for its actions in the war, the brigade was used to form the 3rd Tank Division in mid-1940 after participating in the invasion of Estonia.

[2] One of the two original mechanized corps of the Red Army, the 11th was formed as a result of a massive expansion in Soviet tank production.

During that year, the headquarters of the 11th Mechanized Corps and another of its brigades were relocated to the Transbaikal Military District as a result of rising tensions with Japan.

Korchagin was arrested in August 1937 during the Great Purge, which also claimed six other brigade officers, including the commissar and the chief of engineers.

[5] Three Red Army men were also among those imprisoned, one being sentenced to six years on charges of discrediting the government by "speaking hostilely about the forms and methods of Soviet art".

The threat of an invasion by the 134,000 troops on their border forced the Estonian government into accepting the Soviet ultimatum,[9] and on 2 October the corps moved south with the 8th Army to the vicinity of Ostrov in a repetition of the same tactic against Latvia.

The Latvian government similarly gave in to the threat of the 255,000 troops on their border,[10] and on 13 October the corps left the 8th Army to return to the Leningrad region.

[8] The plans of the 7th Army envisioned a role of deep penetration for the corps: it was to turn west after reaching Kiviniemi and crossing the Vuoksi River in order to surround the Finnish troops on the isthmus.

[13] By the beginning of the Winter War, the personnel of the corps, which also included the 1st Light Tank Brigade and the 15th Motor Rifle and Machine Gun Brigade, were well trained, but their tanks were worn out by the long road marches to the Estonian and Latvian borders and then to the Finnish border, which covered a total distance of 300 kilometers (190 mi).

Two hours later, the battalion moved forward but the breakthrough had in fact not materialized and it was stopped by the first line of dragon's teeth, where a flamethrower tank from the 8th Combat Support Company was set on fire by a direct hit from an artillery shell, killing its driver.

The 13th Brigade remained on the frontline exposed to heavy shelling until they were ordered to pull back on 13:00 on 18 December, losing two tanks burned out and eight disabled with the loss of six tankers killed and twelve wounded.

Soviet tank tactics fundamentally changed: instead of racing ahead of the infantry and exposing themselves to being picked off at close range by grenades and Molotov cocktails while crossing trenches, tanks were now to be positioned in front of the Finnish trenches beyond small arms range and systematically demolish the defensive positions with their guns.

They practiced firing at dragon's teeth, finding that a 45 mm armor-piercing shell hit would destroy the obstacle, a method later used in combat, in addition to towing armored sleds carrying infantrymen to resolve the problem of deep snow slowing down the foot soldiers.

[13] The Soviet offensive began on 11 February with the attack again concentrated along the Vyborg road and within two days the 123rd had broken through the Finnish defenses with tank support.

To pursue the retreating Finnish troops and develop the attack on Vyborg, on 14 February, three mobile groups were created in the 7th Army, which included infantry riding on the tanks.

Moving to the front on crowded roads, they were delayed for hours: the chief of staff of the 13th Brigade recalled that vehicles stood as many as five rows deep.

North of Kämärä station, the group was halted by prepared Finnish defenses on the heights above Lake Mustalampi held by the 3rd Battalion of the 61st Infantry Regiment.

[28] A battle group from the 1st Light Tank Brigade detachment commanded by Senior Lieutenant Boris Kolessa captured Hill 45.0 on 19 February, but their advance was stopped when Finnish infantry blew up the road bridge near Pien-Pero.

At 10:30 on the next day, the road between Mustalampi and Pienperio was cut, isolating Group Baranov, Kolessa's detachment, and elements of the 84th Rifle Division with its commander, and Hill 45.0 was retaken by the Finnish.

Flares and radio messages did not stop the firing and only after the brigade chief of staff personally went to the 84th's command post did it cease.

[29] The rest of the 84th and the 51st Rifle Division slowly arrived at Hill 45.0 between 24 and 27 February, while the brigade lost two tanks on the 24th and a planned attack slated for the 26th could not be conducted because the 84th could not quickly organize artillery preparation.

[26] A postwar NKVD report faulted the brigade command for not coordinating with neighboring units in order to create a continuous line and for insufficient aggressiveness during this period.

On that day, the 13th Tank Battalion captured the outskirts of Pien-Pero and moved on Lintula before occupying the Pero station after the hurried retreat of its defenders, who failed to blow up the bridge there.

The 9th and 15th Tank Battalions with the 348th Regiment of the 51st Division moved along the route from Pillula-Pero and Suur-Pero towards Repola, slowed down by felled trees and landmines in the area of Hill 50.2.

[17] After Soviet troops cut the road between Vyborg and Helsinki, the Finnish were forced to concede and the war ended on 13 March with a cease-fire following the signing of the Moscow Peace Treaty.

[34] Following the success of massed German tank units in the Battle of France, Stalin decided once again to reestablish mechanized corps on 9 June 1940.