The Soviet offensive plans controversy was a debate among historians as to whether Joseph Stalin had planned to launch an attack against Nazi Germany in the summer of 1941. The controversy began with the 1988 book Icebreaker: Who started the Second World War? by former Soviet defector and UK resident Viktor Suvorov. In it, he claimed that Stalin used Nazi Germany as a proxy to attack Europe.

The thesis by Suvorov that Stalin had planned to attack Nazi Germany in 1941 was rejected by a number of historians, but at least partially supported by others. The majority of historians believe Stalin sought to avoid war in 1941 because he believed his military was not prepared to fight German forces, though historians disagree on why Stalin persisted with his appeasement strategy of Nazi Germany despite mounting evidence of an impending German invasion. Suvorov's main argument, that the Soviet government was planning to launch an offensive campaign against Nazi Germany, has been widely discredited as a historical distortion.

The policies of Stalin contributed to the Soviet famine of 1932–1933 which killed millions, including in the Holodomor in Ukraine. Between 1936 and 1938, Stalin executed hundreds of thousands of his real and perceived political opponents in the Great Purge. Under his regime, an estimated 18 million people passed through the Gulag system of forced labour camps, and more than six million people, including kulaks and entire ethnic groups, were deported to remote areas of the country.

The Soviets faced a threat in the east from the expansionist Japanese in the latter part of the 1930s. The Soviet–Japanese border conflicts culminated in the Battles of Khalkhin Gol in 1939. Stalin initiated a military build-up, with the Red Army more than doubling between January 1939 and June 1941. In haste many of its officers were poorly trained. Between 1940 and 1942 Stalin purged the military, leaving it with a severe shortage of trained officers.

In August 1939, the Soviet Union (Stalin) and Nazi Germany (Hitler) signed the Molotov–Ribbentrop Pact with a secret protocol dividing Eastern Europe. On 1 September, Germany started the Invasion of Poland, leading the UK and France to declare war only on Germany. On 17 September the Red Army invaded eastern Poland. On 30 November 1939, the Soviets started invading Finland, starting the Winter War. Despite numerical inferiority, the Finns kept the Red Army at bay. Embarrassed by their inability to defeat the Finns, Stalin signed an interim peace treaty (12 March 1940). In June 1940, while the German Wehrmacht defeated France (Battle of France), the Red Army occupied the Baltic states, which were forcibly merged into the Soviet Union in August. They also invaded and annexed Bessarabia and northern Bukovina, parts of Romania. The speed of the German victory over and occupation of France in mid-1940 took Stalin by surprise. He seemingly focused on appeasement in order to delay conflict. In spring of 1941, Stalin concluded that relations with Germany had deteriorated to such an extent that he needed to become de jure head of government as well, and on 6 May, replaced Molotov as Premier of the Soviet Union.

The Stalin Line fortifications along the western border of the Soviet Union were dismantled in favour of constructing the Molotov Line further west, along the new border of the USSR (Curzon Line). The Axis invasion starting on 22 June 1941 caught the Red Army with the new line unfinished and the Stalin Line largely abandoned and in disrepair, neither was of much use.

Historians have debated whether Stalin was planning an invasion of German territory in the summer of 1941. The debate began in the late 1980s when Viktor Suvorov published a journal article and later the book Icebreaker in which he claimed that Stalin had seen the outbreak of war in Western Europe as an opportunity to spread communist revolutions throughout the continent, and that the Soviet military was being deployed for an imminent attack at the time of the German invasion. This view had also been advanced by former German generals following the war. Suvorov's thesis was fully or partially accepted by a limited number of historians, including Valeri Danilov, Joachim Hoffmann, Mikhail Meltyukhov, and Vladimir Nevezhin and attracted public attention in Germany, Israel, and Russia. It has been strongly rejected by most historians and Icebreaker is generally considered to be an "anti-Soviet tract" in Western countries. David Glantz and Gabriel Gorodetsky wrote books to rebut Suvorov's arguments. The majority of historians believe that Stalin was seeking to avoid war in 1941, as he believed that his military was not ready to fight the German forces.

According to Professor Alexander Hill, it is currently (2012) believed that whereas the war against "capitalist powers" was seen as potentially inevitable by Soviet leadership, the Soviet Union was making some preparations for war, and the Soviet pursuit for a collective security system in Europe ("Litvinov's line") was sincere in the late 1930s, the event that triggered active Soviet war preparations was the rapid collapse of the Anglo-French alliance in June 1940. British historian Evan Mawdsley wrote in his book "Thunder in the East: The Nazi-Soviet War, 1941–1945":