|The following is based on the Soviet campaign for Red Alert 3: Uprising and has not been confirmed by canon sources.|
Dasha Fedorovich, the resistance leader, at the headquarters of the Soviet Underground
After the Soviet Union's defeat in the War of the Three Powers, remnants of the Soviet military established a resistance movement, intending to restore the union. The Soviet Underground came into conflict with the FutureTech corporation several times during the Uprising following the war.
After the Third World War, the Allies took control of the USSR, setting up a puppet government. While European Union President Rupert Thornley reassured the general public that the Soviet people welcomed the Allies with open arms, this was not the case.
Soviet intelligence officer Dasha Fedorovich, technically being a civilian, had avoided capture. Because the Allies were spread thin trying to demilitarize the Empire of the Rising Sun at the same time, she, along with several other brave and well-connected Soviet patriots, quickly seized the opportunity to form a resistance movement, intent to restore the Union to greatness.
In a testament to the pride and determination of the Soviet spirit, the surviving forces of the Union's military soon rallied after the defeat of their corrupt leaders at Leningrad, in spite of countless losses and setbacks. Although the Soviet military now is but a shadow of its former self, some of its most talented commanders are working tirelessly to carry their nation forward.
Sometime after the war, the organization discovered that several Soviet scientists had been captured by the Allies. After rescuing them, they realized that it was actually FutureTech that kidnapped the scientist, forcing them to develop new weapons.
After rescuing the scientists, the resistance locates another FutureTech facility in Russia itself, and discovers that it has been experimenting on captured civilians. This facility proved to be heavily defended, and even shot down two Kirov Airships sent to level it with the latest cryo weapons that it was testing. In the end, however, it was also destroyed.
Tracing the source of FutureTech reinforcements, the Soviets discover a military base in Yucatan, one that not even the Allies know of. During the attack on that base, they discover that the Sigma Harmonizer that FutureTech has been building is in reality a weapon capable of stopping time.
Racing against time, the Soviet forces attack Sigma Island, destroying the FutureTech production facilities there and stopping the Sigma Harmonizer's activation. With this, Rupert Thornley's plan to crush the Soviet resistance with the Sigma Harmonizer was foiled, and FutureTech was discredited. Allied occupational forces, thanked the Soviet Underground, and pulled their forces out of the USSR to increase security in their own territories.