RDS-6s is the codename for a hydrogen bomb the Soviet Union detonated on August 12, 1953. The bomb detonation was done as a test at the Semipalatinsk test site, which is current day Northern Kazakhstan. The bomb detonated a force measured at 400 kilotons (400,000 tons) of TNT.

“Work on the super-bomb had begun in 1946, three years before the Soviet Union exploded its first atomic bomb. The project was organized by the First Chief Directorate under Lavrentii Beria, Minister of State Security (MGB)” (Siegelbaum). Igor Kurchatov, a physicist who had been appointed scientific director of the Soviet Union’s nuclear project in 1943, headed the program. “The design for the bomb was based on the ‘layer cake’ concept developed by the physicist Andrei Sakharov (1921-89), according to which alternate layers of thermonuclear material and uranium-238 were placed in a fission bomb” (Siegelbaum).

But the test was done in reaction to US bomb development, “RDS-6 was part of the Soviet Union’s efforts to catch up with the United States, which had detonated its first thermonuclear device with the ‘George’ test two years earlier in May 1951” (ctbto.org). Developing a strong nuclear arms program was crucial to Stalin. The world was advancing, and Stalin wanted the Soviet Union to be a powerful factor amongst world powers, and developing such devastating weapons would give the country that legitimacy. Even after Stalin’s death, the nuclear program continued to advance. The Soviets even used the RDS-6s detonation as leverage against the US, claiming they (the Soviets) not only had a hydrogen bomb, but that they had the capability of deploying it by air.

There were political setbacks for the Soviets, however, with the testing of this hydrogen bomb, “In a speech on March 1954, Georgii Malenkov, chairman of the Council of Ministers, referred to the danger of ‘a new world war, which with modern weapons means the end of world civilization.’ Raising this specter went beyond what Khrushchev and other party leaders were willing to acknowledge publicly, and even though he subsequently reverted to the standard line that nuclear aggression by the United States would lead to the ‘collapse of the capitalist social system,’ Malenkov could not undo the damage to his own political career” (Siegelbaum).

Throughout this time period both the US and the Soviet sought to advance their nuclear programs, and both had catastrophic consequences for surrounding populations, “The largest [test ever carried out by the US], Castle Bravo, yielded 15 megatons and created the worst radiological disaster in U.S. history. Several of the Marshall Islands’ atolls, including one where U.S. servicemen were stationed, were blanketed with fallout. The Japanese fishing vessel ‘Lucky Dragon Number 5’ was also heavily contaminated, causing the death of at least one crewman. This incident created an international uproar and a diplomatic crisis with Japan. One year later, the Soviet Union drew level with its own ‘true’ two-stage hydrogen bomb, codenamed RDS-37. A total of over 2,000 nuclear tests worldwide were conducted at the Semipalatinsk Test Site in modern-day Kazakhstan. More than a million residents were exposed to radiation. The region has reported a surge in cancer rates and birth defects” (ctbto.org).


Hydrogen Bomb




Operation Iskra

*This post was recognized in the Comrades’ Corner (week 7)

Operation Iskra, also known as Operation Spark, was a military operation conducted by the Red Army to break the Leningrad Blockade in 1943.

The Siege of Leningrad began in 1941, as the Germans began surrounding the city and cutting off supply routes for food and goods. Throughout 1942 the Soviets launched multiple offensive attacks to retake Leningrad, but the Germans managed to hold the city. By late 1942, the Soviets were weakening the German fronts during the Battle of Stalingrad. During that same time, plans were drawn up for Operation Iskra, in order to hammer the Germans while they were weak.

The Germans managed to trap thousands of civilians inside the city while they blocked off the supply routes. With hardly enough food to last the upcoming winter, civilians and soldiers began to die of starvation and the harsh winter conditions, “Winter came early, and was one of the coldest winters on record. By November the people were on starvation rations. In December children’s sleds began to appear. But they weren’t carrying kids out having fun . . . ‘The squeak, squeak, squeak of the runners sounded louder than the shelling. It deafened the ears. On the sleds were the ill, the dying, the dead'” (Zimmerman). Some civilians managed to escape and migrate out of the city, but for those that had already lost their lives, their bodies were piled together and burned.

The Red Army launched its operation against the German front on January 12, 1943. It was the Soviet’s third attempt to retake the city, and this time, the Soviets were serious, “At 9:30 am, on January 12, 1943, Govorov and Merestkov opened Operation Spark with the thunder of 4,500 artillery pieces. One gun was positioned for every 20 feet of front line. On top of the artillery, the heavy naval guns of the Red Fleet in Leningrad harbor joined in the bombardment. Bridges, buildings, trenches, and trees exploded and collapsed in showers of steel, earth, and wood” (WHN Staff). The battle lasted until January 30, 1943 with the Soviets making slow but steady advances into the city, day by day.

By January 22, the Soviets began building railroads to connect the city to the rest of the country in order to reestablish supply lines. Within a month, the railroad was complete and the Soviets were able to begin effectively transporting supplies in and out of the city.


“By January 30, it [The Red Army] had reached Leningrad and established a 5 to 6 mile wide corridor along the southern shore of Lake Ladoga. Though supply convoys were within range of German artillery, and the siege had many months yet to go, Leningrad had been saved” (Zimmerman).

Operation Iskra was a success for the Soviet forces. They were able to regain their city and reestablish supply lines for civilian and military personnel, in and outside of the city. Soviet leaders Govorov and Zhukov were both promoted that year following their victory in the operation. While their success with Operation Iskra was crucial, Soviet advances into neighboring cities turned out to be a struggle. The Soviets found themselves only making slow advances with not much to be gained.

Firsthand account of Operation Iskra:



Leningrad & Operation Spark: Breaking the Nazi Stranglehold