The United States maintained military bases and nuclear weapons in South Korea, which the Soviet Union viewed as a threat to its security.

Gorbachev desired foreign capital and high technology, as well as Seoul's help in alleviating the Soviet economic crisis through direct investment, joint ventures, and trade.

As early as May 1979, South Korea signed an agreement obtaining Finnish assistance in exporting to the Soviet Union and Eastern Europe.

[5] In the 1980s, South Korean President Roh Tae-woo's Nordpolitik and Mikhail Gorbachev's "New Thinking" were both attempts to reverse their nations' recent histories.

Gorbachev had signaled Soviet interest in improving relations with all countries in the Asia-Pacific region, including South Korea, as explained in his July 1986 Vladivostok and August 1988 Krasnoyarsk speeches.

South Korea's expanding trade with Eastern Europe and the Soviet Union initially was encouraged by the United States, although Washington later became increasingly concerned over possible high-technology transfers.

Because of the lack of diplomatic relations, most South Korean-Soviet trade initially was indirect; Eastern Europe, Hong Kong, Japan, and Singapore served as intermediaries.

Several major South Korean businesses including Daewoo, Sunkyong, and Lucky-Goldstar traded directly with the Soviet Union in 1990.

[5] South Korea's new-found wealth and technological prowess had been attracting the interest of a growing number of socialist nations.

In initiating Nordpolitik, Roh's confidential foreign policy adviser was rumored to have visited Moscow to consult with Soviet policymakers.

[5] In June 1990, Roh held his first summit with President Gorbachev in San Francisco and diplomatic relations between the two countries officially began on September 30, 1990.

On November 20, 1992 Russia and South Korea signed a protocol providing for regular visits of defence officials and naval vessels between the two countries.

[12] On August 28, 2018, Vice Defense Minister Suh Choo-suk met with Russian counterpart Alexander Fomin and reached an agreement to install a direct communication line between their air forces of two countries.

[14] In June 2024, as part of a Russian state visit to North Korea, the two countries signed a mutual defense pact.

Reports indicate that North Korean special forces have been trained in Russia, with footage emerging of them receiving military uniforms.

[19] In December 2024, the Financial Times reported that leaked Russian documents outlined plans for Russia to attack South Korea in the event of a wider conflict.

Russia said that it will work with Seoul on a new U.N. Security Council resolution and to revive international talks on the North Korean nuclear issue.

Most of Koryo-saram were deported to Soviet Central Asia (Uzbekistan and Kazakhstan) in 1937 as part of Stalin's policy of "frontier cleansing".

Unlike the communities on the Russian mainland, which consist mostly of immigrants from the late 19th and early 20th centuries, the ancestors of the Sakhalin Koreans came as immigrants from Gyeongsang and Jeolla provinces in the late 1930s and early 1940s, forced into service by the Japanese government to work in coal mines in order to fill labour shortages caused by World War II.