1953 Cambodia becomes independent from France.
1955 King Norodom Sihanouk of Cambodia abdicates the throne in favor of his father, King Norodom Suramarit.
1955 Albania, Austria, Bulgaria, Cambodia, Finland, Hungary, Ireland, Italy, Jordan, Laos, Libya, Nepal, Portugal, Romania, Spain and Sri Lanka join the United Nations.
1958 A parcel bomb sent by Ngo Dinh Nhu, younger brother and chief adviser of South Vietnamese President Ngo Dinh Diem, fails to kill King Norodom Sihanouk of Cambodia.
1967 Vietnam War: In a propaganda ceremony in Phnom Penh, Cambodia, three American prisoners of war are released by the Viet Cong and turned over to "new left" antiwar activist Tom Hayden.
1969 The United States begins secretly bombing the Sihanouk Trail in Cambodia, used by communist forces to infiltrate South Vietnam.
1970 Lon Nol ousts Prince Norodom Sihanouk of Cambodia.
1970 Vietnam War: U.S. President Richard M. Nixon formally authorizes American combat troops to fight communist sanctuaries in Cambodia.
1970 Vietnam War: United States and South Vietnamese forces invade Cambodia to hunt Viet Cong.
1970 Protests erupt in Seattle, Washington, following the announcement by U.S. President Richard Nixon that U.S. Forces in Vietnam would pursue enemy troops into Cambodia, a neutral country.
1970 Vietnam War: Kent State shootings: the Ohio National Guard, sent to Kent State University after disturbances in the city of Kent the weekend before, open fire killing four students and wounding nine others. The students were protesting the United States' invasion of Cambodia.
1970 The Khmer Republic is proclaimed in Cambodia.
1970 U.S. President Richard Nixon asks the U.S. Congress for $155 million USD in supplemental aid for the Cambodian government.
1971 In Cambodia, Khmer Rouge forces attack the city of Phnom Penh and its airport, killing 44, wounding at least 30 and damaging nine aircraft.
1971 Cambodian Civil War: Khmer Rouge rebels intensify assaults on Cambodian government positions, forcing their retreat from Kompong Thmar and nearby Ba Ray.
1973 The United States Senate votes to cut off funding for the bombing of Khmer Rouge targets within Cambodia, hastening the end of the Cambodian Civil War.
1973 Vietnam War: In testimony by Assistant Secretary of Defense Jerry Friedheim to the US Senate Committee on Armed Services, the US Defense Department admits it lied to US Congress about bombing Cambodia .
1973 Vietnam War: The United States bombing of Cambodia ends.
1975 The Cambodian Civil War ends. The Khmer Rouge captures the capital Phnom Penh and Cambodian government forces surrender.
1975 Mayagüez incident: the Cambodian navy seizes the American merchant ship {{SS|Mayaguez}} in international waters.
1976 Cambodia is renamed the Democratic Kampuchea by the Khmer Rouge.
1976 Prince Norodom Sihanouk resigns as leader of Cambodia and is placed under house arrest.
1991 Cambodian Prince Norodom Sihanouk returns to Phnom Penh after thirteen years of exile.
1998 Leaders of the Khmer Rouge apologize for the 1970s genocide in Cambodia that claimed over 1 million lives.
1999 Cambodia joins the Association of Southeast Asian Nations (ASEAN) bringing the number of members to 10.
2004 King Norodom Sihanouk of Cambodia abdicates.
2009 Typhoon Ketsana (2009) hit the Philippines, China, Vietnam, Cambodia, Laos and Thailand, causing 700 fatalities.