In October 1964, the Communist Party of the Soviet Union underwent a substantial leadership change, with Leonid Brezhnev becoming the General Secretary, replacing Nikita Khrushchev. Brezhnev's rise to power was initially facilitated by a coalition of party leaders concerned about Khrushchev's erratic policy-making, particularly following the Cuban Missile Crisis. Alexei Kosygin also took on a pivotal role, becoming the Chairman of the Council of Ministers, a position that placed him at the forefront of government administration. This leadership transition happened during the Central Committee Plenary meeting, a critical point in the Soviet Union's political landscape, as it set the stage for Brezhnev's lengthy rule that would last until 1982.

Brezhnev's leadership is characterized by a more cautious and stable approach to governance. He emphasized the importance of collective leadership, which sought to address the discontent among party officials stemming from Khrushchev's more aggressive reform policies. Concurrently, Kosygin's government faced the challenge of managing the economy amid growing stagnation, marking the beginning of a period that historians would later describe as 'developed socialism'. This era was notable for its emphasis on maintaining stability within the Communist Party while confronting the realities of a globalized world.

The newly established leadership marked a departure from Khrushchev's policies, which had focused on de-Stalinization and greater openness. Brezhnev's era ushered in a paradigm of increased state control and a more militaristic foreign policy, epitomized by the expansion of the Soviet military's reach. The 1964 transition set the groundwork for subsequent Soviet dealings during the Cold War, impacting relations with both Western nations and Eastern Bloc countries.