More information about the Republic of Korea is available on the Republic of Korea and from other Department of State publications and other sources listed at the end of this fact sheet.


The United States and Korea’s Joseon Dynasty established diplomatic relations under the 1882 Treaty of Peace, Amity, Commerce, and Navigation, and the first U.S. diplomatic envoy arrived in Korea in 1883. U.S.-Korea relations continued until 1905, when Japan assumed direction over Korean foreign affairs. In 1910, Japan began a 35-year period of colonial rule over Korea. Following Japan’s surrender in 1945, at the end of World War II, the Korean Peninsula was divided at the 38th parallel into two occupation zones, with the United States in the South and the Soviet Union in the North. Initial hopes for a unified, independent Korea were not realized, and in 1948 two separate nations were established — the Republic of Korea (R.O.K.) in the South, and the Democratic People’s Republic of Korea (DPRK) in the North. In 1949, the United States established diplomatic relations with the Republic of Korea.

On June 25, 1950, North Korean forces invaded the R.O.K.. Led by the United States, a United Nations coalition of 16 countries undertook its defense. Following China’s entry into the war on behalf of North Korea later that year, a stalemate ensued for the final two years of the conflict until an armistice was concluded on July 27, 1953. A peace treaty has never been signed. In 1953, at the conclusion of the Korean War, the United States and the Republic of Korea signed a Mutual Defense Treaty, the foundation of a comprehensive alliance that endures today.

In the decades after the war, the R.O.K. experienced political turmoil under autocratic leadership, but developed a vocal civil society that led to strong protests against authoritarian rule. Pro-democracy activities intensified in the 1980s and the R.O.K. began the transition to what is now a vibrant, democratic system. U.S.-R.O.K. ties are based on common values of democracy, human rights, and the rule of law.

The United States and the R.O.K. share a long history of friendship and cooperation based on shared values and interests. The two countries work together to combat regional and global threats and to strengthen their economies. The United States has maintained Army, Air Force, Navy, and Marine personnel in the R.O.K. in support of its commitment under the U.S.-R.O.K. Mutual Defense Treaty to help the R.O.K. defend itself against external aggression. In 2013, the two countries celebrated the 60th anniversary of the U.S.-R.O.K. alliance. A Combined Forces Command coordinates operations between U.S. units and R.O.K. armed forces. The United States and the R.O.K. coordinate closely on the North Korean nuclear issue and the denuclearization of the Korean Peninsula. As the R.O.K.’s economy has developed (it joined the OECD in 1996), trade and investment ties have become an increasingly important aspect of the U.S.-R.O.K. relationship.

In recent years, the U.S.-R.O.K. alliance has expanded into a deep, comprehensive global partnership, and the R.O.K.’s role as a regional and global leader continues to grow. The R.O.K. hosted the 2010 G-20 Summit, the 2011 Fourth High-Level Forum on Aid Effectiveness, the 2012 Nuclear Security Summit, the 2013 Seoul Conference on Cyberspace, and the 2014 International Telecommunication Union Plenipotentiary Conference. In 2017, the R.O.K. chaired the Global Health Security Agenda Steering Group. The R.O.K. is a committed member of various international nonproliferation regimes, including the Proliferation Security Initiative (PSI) and the Global Initiative to Combat Nuclear Terrorism (GICNT). The R.O.K. has pledged more than half a billion dollars towards development efforts including health security, women’s empowerment, and humanitarian assistance.

The emergence of the R.O.K. as a global leader has led to an increasingly dynamic U.S.-R.O.K. Alliance focused on future-oriented partnership opportunities including space, energy, health, climate change, and cyber. The United States and R.O.K. renewed in 2015 the Civil Nuclear “123” Agreement and maintain a High-Level Bilateral Commission to address civil nuclear issues of mutual interest. Our two countries signed in 2016 a Civil Space Framework Agreement to increase cooperation in civil space exploration and we hold biennial cabinet-level Joint Committee Meetings on science and technology. The R.O.K. is an active partner on efforts combat illegal, unregulated, and unreported fishing, and is working to establish a World Fisheries University.

People-to-people ties between the United States and the R.O.K. have never been stronger are strong. The R.O.K. is a top three origin country in absolute terms for international students attending U.S. colleges and universities. Educational exchanges include a vibrant Fulbright exchange program as well as the Work, English Study, and Travel (WEST) program that gives a diverse group of Korean students the opportunity to learn more about the United States.

Underscoring the strength of the U.S.-R.O.K. alliance, President Moon’s first overseas trip after his inauguration was to the United States in June 2017. In November 2017, President Trump made the first state visit to the Republic of Korea by a U.S. President in 25 years.

U.S. Assistance to the Republic of Korea

The United States provides no development assistance to the R.O.K.. The R.O.K., a recipient of U.S. assistance in the years after the Korean War, is a development aid donor today.

Bilateral Economic Relations

Over the past several decades, the R.O.K. has achieved a remarkably high level of economic growth and is now the United States’ sixth-largest goods trading partner with a trillion-dollar economy. Major U.S. firms have long been leading investors, while the R.O.K.’s top firms have made significant investments in the United States. There are large-scale flows of manufactured goods, agricultural products, services, and technology between the two countries. R.O.K. foreign direct investment in the United States has nearly doubled since 2011 from $19.7 billion to $38.8 billion in 2016, making the Republic of Korea the second largest Asian source of foreign direct investment into the United States. During President Trump’s 2017 visit to the Republic of Korea, R.O.K. companies announced plans to begin a series of projects in the United States over the next four years valued at $17.3 billion. The Korea-U.S. Free Trade Agreement (KORUS FTA) entered into force on March 15, 2012, underscoring the depth of bilateral trade ties. In March 2018, the United States and the Republic of Korea reached an agreement on the renegotiation of the KORUS FTA.

The Republic of Korea’s Membership in International Organizations

The R.O.K. and the United States belong to a number of the same international organizations, including the United Nations, G-20, Organization for Economic Cooperation and Development, Asia-Pacific Economic Cooperation forum, Association of Southeast Asian Nations (ASEAN) Regional Forum, International Monetary Fund, World Bank, and World Trade Organization. The R.O.K. hosts the Green Climate Fund, an international organization associated with the United Nations Framework Convention on Climate Change. The R.O.K. also is a Partner for Cooperation with the Organization for Security and Cooperation in Europe and an observer to the Organization of American States.

Bilateral Representation

The Ambassador-Designate is Harry Harris Jr. The U.S. Chargé d’Affaires ad interim is Marc Knapper; other principal embassy officials are listed in the Department’s Key Officers List.

The R.O.K. maintains an embassy in the United States at 2450 Massachusetts Avenue NW, Washington, DC 20008 (tel. 202-939-5600).

More information about South Korea is available from the Department of State and other sources, some of which are listed here:

CIA World Factbook South Korea Page
International Travel Information for South Korea
U.S. Embassy
U.S. American Presence Post Busan
Embassy of the Republic of Korea in Washington, DC
U.S.-Republic of Korea Free Trade Agreement
U.S. Forces Korea
Office of the U.S. Trade Representative Countries Page
U.S. Census Bureau Foreign Trade Statistics International Offices Page
Library of Congress Country Studies
Travel Information

U.S. Department of State

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