Reunified

Vietnam Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...

follows

Indochina Time UTC+07:00 is an identifier for a time offset from UTC of +07:00. In ISO 8601 the associated time would be written as . It is 7 hours ahead of UTC, meaning that when the time in UTC areas is midnight (00:00), the time in UTC+07:00 areas would ...

(ICT), which is seven hours ahead of UTC, ICT is used all year round as Vietnam does not observe

daylight saving time Daylight saving time (DST), also referred to as daylight savings time or simply daylight time (United States, Canada, and Australia), and summer time (United Kingdom, European Union, and others), is the practice of advancing clocks (typicall ...

. Vietnam shares the same time zone with

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...

Cambodia Cambodia (; also Kampuchea ; km, កម្ពុជា, UNGEGN: ), officially the Kingdom of Cambodia, is a country located in the southern portion of the Indochinese Peninsula in Southeast Asia, spanning an area of , bordered by Thailan ...

Christmas Island Christmas Island, officially the Territory of Christmas Island, is an Australian external territory comprising the island of the same name. It is located in the Indian Ocean, around south of Java and Sumatra and around north-west of the ...

, Laos, and Western

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

. Vietnam referenced

ISO 8601 ISO 8601 is an international standard covering the worldwide exchange and communication of date and time-related data. It is maintained by the Geneva-based International Organization for Standardization (ISO) and was first published in 1988, w ...

under in 1998 and then created its own standard TCVN 6398-1:1998.

History

* After Phủ Liễn Observatory was built, French Indochina announced all states (consisting of north-Vietnamese

Tonkin Tonkin, also spelled ''Tongkin'', ''Tonquin'' or ''Tongking'', is an exonym referring to the northern region of Vietnam. During the 17th and 18th centuries, this term referred to the domain '' Đàng Ngoài'' under Trịnh lords' control, includ ...

, central-Vietnamese Annam, south-Vietnamese

Cochinchina Cochinchina or Cochin-China (, ; vi, Đàng Trong (17th century - 18th century, Việt Nam (1802-1831), Đại Nam (1831-1862), Nam Kỳ (1862-1945); km, កូសាំងស៊ីន, Kosăngsin; french: Cochinchine; ) is a historical exony ...

, as well as

, Laos and Chinese

Guangzhouwan The Leased Territory of Guangzhouwan, officially the , was a territory on the coast of Zhanjiang in China leased to France and administered by French Indochina. The capital of the territory was Fort-Bayard, present-day Zhanjiang. The Japan ...

) were part of 104°17′17″E longitude east of Paris meridian 2°20′14″E, or 106°37′30″E from

Greenwich Mean Time Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London, counted from midnight. At different times in the past, it has been calculated in different ways, including being calculated from noon; as a con ...

from 00:00, 1 July 1906 onward. * In 1911,

Metropolitan France Metropolitan France (french: France métropolitaine or ''la Métropole''), also known as European France (french: Territoire européen de la France) is the area of France which is geographically in Europe. This collective name for the European ...

adopted UTC±00:00 (the

solar time Solar time is a calculation of the passage of time based on the position of the Sun in the sky. The fundamental unit of solar time is the day, based on the synodic rotation period. Two types of solar time are apparent solar time (sundial ti ...

Greenwich Greenwich ( , ,) is a town in south-east London, England, within the ceremonial county of Greater London. It is situated east-southeast of Charing Cross. Greenwich is notable for its maritime history and for giving its name to the Greenwich ...

) as its official time, and used it until 1940 (with UTC+01:00 used during the summers from 1916 to 1940), forcing French Indochina observed UTC+07:00 from 00:00, 1 May 1911. * Following change in time zone of Vichy authorities, French Indochina was integrated to UTC+08:00 skipping 60 minutes at 23:00, 31 December 1942. * The

Empire of Japan The also known as the Japanese Empire or Imperial Japan, was a historical nation-state and great power that existed from the Meiji Restoration in 1868 until the enactment of the post-World War II Constitution of Japan, 1947 constitu ...

occupied Vichy French Indochina fully. Indochinese regions thereafter followed Tokyo time zone (UTC+09:00), skipping 60 minutes at 23:00, 14 March 1945. * By August General Uprising, the Fall of Empire of Vietnam and the

Proclamation of Independence of the Democratic Republic of Vietnam The Proclamation of Independence of the Democratic Republic of Vietnam ( vi, Tuyên ngôn độc lập Việt Nam Dân chủ Cộng hòa) was written by Hồ Chí Minh, and announced in public at the Ba Đình flower garden (now the Ba Đình ...

, Provisional Uniform Government of the

Democratic Republic of Vietnam North Vietnam, officially the Democratic Republic of Vietnam (DRV; vi, Việt Nam Dân chủ Cộng hòa), was a socialist state supported by the Soviet Union (USSR) and the People's Republic of China (PRC) in Southeast Asia that existed f ...

took control, announcing UTC+07:00 as official time zone on 2 September 1945. Whilst, the then under-attack regions of Vietnam, Laos and Cambodia adopted UTC+08:00 and non-attacked regions (at the time and even after the

1954 Geneva Conference The Geneva Conference, intended to settle outstanding issues resulting from the Korean War and the First Indochina War, was a conference involving several nations that took place in Geneva, Switzerland, from 26 April to 20 July 1954. The part ...

) adopted UTC+07:00 from

April 1 Events Pre-1600 * 33 – According to one historian's account, Jesus Christ's Last Supper is held. * 527 – Byzantine Emperor Justin I names his nephew Justinian I as co-ruler and successor to the throne. *1081 – Alexios I Ko ...

, 1947: Laos (part of Indochina) from 15 April 1954, Hanoi from October 1954, Haiphong from May 1955. * Under control of State of Vietnam, South Vietnam adopted UTC+07:00 from 00:00, 1 July 1955. *South Vietnam time zone was changed to UTC+08:00 from 23:00, 31 December 1959, passing 60 minutes. *North Vietnam confirmed official UTC+07:00 from 1 January 1968. *Following the

Fall of Saigon The Fall of Saigon, also known as the Liberation of Saigon by North Vietnamese or Liberation of the South by the Vietnamese government, and known as Black April by anti-communist overseas Vietnamese was the capture of Ho Chi Minh City, Saigon, t ...

in April–May 1975, reunified Vietnam then observes UTC+07:00 with Saigon (and other southern parts) delaying 60 minutes on 13 June 1975.

Time in
French Indochina French Indochina (previously spelled as French Indo-China),; vi, Đông Dương thuộc Pháp, , lit. 'East Ocean under French Control; km, ឥណ្ឌូចិនបារាំង, ; th, อินโดจีนฝรั่งเศส, ...

Time in
North Vietnam North Vietnam, officially the Democratic Republic of Vietnam (DRV; vi, Việt Nam Dân chủ Cộng hòa), was a socialist state supported by the Soviet Union (USSR) and the People's Republic of China (PRC) in Southeast Asia that existed f ...

Time in South Vietnam

Time in Reunified Vietnam

References

Bibliography

* Trần Tiến Bình (2005), ''Lịch Việt Nam thế kỷ XX-XXI (1901–2100)'', Nhà xuất bản Văn hoá Thông tin, Hanoi. {{Asia topic, Time in