The following is a chronology of major developments leading up to Sunday's third meeting between U.S. President Donald Trump and North Korean leader Kim Jong Un in the Demilitarized Zone on the border of the two Koreas.
1945 -- The Korean Peninsula is liberated from Japan's colonial rule with its World War II surrender.
1948 -- The peninsula is divided into the Soviet-supported North and the U.S.-backed South.
1950 -- The Korean War begins.
1953 -- The Korean War ends in an armistice.
1985 -- North Korea becomes a signatory to the Nuclear Non-Proliferation Treaty.
1992 -- North and South Korea sign a joint declaration on the denuclearization of the peninsula.
1994 -- Jimmy Carter becomes the first former U.S. president to visit North Korea. The United States and North Korea sign the Agreed Framework under which Pyongyang promises to freeze its nuclear program in return for aid.
2000 -- The first inter-Korean summit takes place in Pyongyang. U.S. Secretary of State Madeleine Albright visits North Korea.
2002 -- Japanese Prime Minister Junichiro Koizumi makes a historic visit to North Korea, during which Pyongyang admits to having abducted Japanese nationals in the 1970s and 1980s.
2003 -- North Korea withdraws from the NPT. The first round of six-party nuclear talks involving the two Koreas, China, Japan, Russia and the United States is held in Beijing.
2005 -- North Korea declares it has nuclear weapons. The six countries adopt a joint statement that commits North Korea to giving up its nuclear program in return for energy aid and security assurances.
2006 -- North Korea conducts its first nuclear test.
2009 -- North Korea says it will quit the six-party talks and carries out its second nuclear test.
2011 -- North Korean leader Kim Jong Il dies and is succeeded by his youngest son, Kim Jong Un.
2012 -- North Korea agrees to implement a moratorium on its nuclear and missile programs in return for food aid from the United States. But it effectively scraps the deal with a test widely seen as aimed at improving its missile capabilities.
2013 -- North Korea conducts its third nuclear test.
2014 -- North Korea test-fires a medium-range Rodong ballistic missile for the first time since 2009.
2015 -- North Korea says it will restart all of its nuclear facilities.
January 2016 -- North Korea announces its first hydrogen bomb test or fourth nuclear test.
May -- North Korea's ruling party holds its first congress in 36 years.
September -- North Korea conducts its fifth nuclear test.
January 2017 -- Kim says North Korea is in the final phase of preparing to test-launch an intercontinental ballistic missile. Donald Trump takes office as U.S. president.
June -- North Korea releases American university student who fell into a coma while imprisoned. He later dies.
July -- North Korea claims its first successful test of an intercontinental ballistic missile.
August -- Trump and North Korea begin to exchange increasingly fiery rhetoric.
September -- North Korea conducts its sixth and most powerful nuclear test.
November -- Trump announces relisting of North Korea as a state sponsor of terrorism. North Korea announces its launch of a new ICBM capable of striking anywhere in the United States with a nuclear warhead and declares its nuclear force as complete.
Jan. 1, 2018 -- Kim says in his New Year address that North Korea is now "capable of thwarting and countering any nuclear threats from the United States." He also offers to send athletes to the Winter Olympics in South Korea.
Jan. 4 -- South Korea and the United States agree to postpone their annual military drills until after the Winter Olympics and Paralympics.
Jan. 9 -- North and South Korea hold their first official talks in more than two years in the truce village of Panmunjeom.
March 25 -- Kim makes a surprise visit to China by train to meet with Chinese President Xi Jinping in Beijing, marking his first overseas trip and his first talks with a foreign leader since taking power in 2011.
April 9 -- Trump says he will meet Kim in May or early June.
April 20 -- North Korea decides to shut down its Punggye-ri nuclear test site and suspend ICBM tests.
April 27 -- Kim and South Korean President Moon Jae In meet on the southern side of the truce village for the first inter-Korean summit in over a decade and agree to work toward "complete" denuclearization of the Korean Peninsula.
May 10 -- Trump says he will meet Kim on June 12 in Singapore.
May 24 -- North Korea says its only known nuclear site in Punggye-ri "completely" dismantled. Trump cancels the scheduled summit with Kim.
May 26 -- Kim and Moon hold a surprise meeting on the North Korean side of the truce village after Trump revives hopes of the summit in Singapore.
June 1 -- Trump meets high-ranking North Korean official at the White House and is given a letter from Kim. Trump reinstates his summit with Kim for the original date in Singapore.
June 12 -- Trump and Kim meet in Singapore in the first summit between the sitting leaders of the United States and North Korea. They sign a joint declaration in which North Korea promises to work toward "complete denuclearization" of the peninsula and the United States pledges to provide security guarantees for Pyongyang.
Sept. 18-20 -- Kim and Moon meet for their third summit in Pyongyang. Kim tells Moon he is prepared to dismantle Yongbyon nuclear complex.
Oct. 7 -- U.S. Secretary of State Mike Pompeo meets with Kim in Pyongyang.
Jan. 1, 2019 -- Kim says he is willing to meet Trump "anytime" and pledges not to make and test any more nuclear weapons.
Jan. 18 -- Kim Yong Chol, a close aide to leader Kim, meets with Trump in Washington.
Feb. 27-28 -- Trump and Kim hold talks in Hanoi, Vietnam, in second summit, but meeting ends abruptly with no agreement.
April 12 -- Kim, in speech, sets year-end deadline for United States to shift stance in nuclear talks.
May 4 -- North Korea fires short-range projectiles.
May 9 -- North Korea fires short-range ballistic missiles.
May 10 -- Trump shrugs off ballistic missiles fired by North Korea as "very standard stuff," and says it was not breach of trust.
June 5 -- Trump says he looks forward to meeting Kim "at the appropriate time."
June 29 -- Trump expresses willingness to meet with Kim at DMZ.
June 30 -- Trump goes to Panmunjeom truce village within DMZ on visit to South Korea, holds third meeting with Kim and agrees to resume stalled nuclear talks within weeks. South Korean President Moon Jae In accompanies Trump.
