In December 1975, the Politburo of the Central Committee of the Vietnam Workers' Party issued a Resolution on the adjustment and consolidation of a number of provinces in the Southern of Vietnam, of which the two provinces of Sa Đéc and Kiến Phong were expected to merge. In February 1976, the Decree of the Provisional Revolutionary Government Council of the Republic of South Vietnam officially named Đồng Tháp province.

Đồng Tháp feudal period

In the past, Đồng Tháp was formerly located in a large and fertile land area due to the Vietnamese immigrants in the North who came to exploit and establish a business to form residential areas. Along with the Southern progress of the natural migration lines, the Nguyễn Lords also gradually established their sovereignty and established the governing apparatus.

History records: At the beginning of the country, depending on the land, a warehouse was located (called a treasury), where the warehouse was located to get the name of the land there to collect money for grain production. The Lord saw that Gia Định province was large enough to set up nine private warehouses, including Quy An, Quy Hóa, Cảnh Dương, Thiên Mụ, Quản Thảo, Hoàng Lap, Tam Lạch, Bả Canh, and Tân Thịnh. In particular, the Ba Cảnh treasury (from 1732 in Định Viễn province) is now the land in the north of Tiền river, Đồng Tháp province.

In 1757, Martial Prince Nguyễn Phước Khoát expanded Tầm Phong Long land between Tiền and Hậu rivers, assigned Nguyễn Cư Trinh to establish three religions: Châu Đốc (in Hậu Giang), Tân Châu (in Tiền Giang) and Đông Khẩu (from Sa Đéc) all belong to Long Hồ palace. In which, Đông Khẩu religion now belongs to the south of Tiền river, Đồng Tháp province.

During the Nguyễn Dynasty, the land that is now in Đồng Tháp was located on the land of Định Viễn, Vĩnh Thanh town, and Kiến An, Định Tường town. In 1832, King Minh Mạng carried out extensive administrative reform, establishing 06 provinces in Cochinchina (called Nam Kỳ Lục province) including: Biên Hòa, Gia Định, Định Tường, Vĩnh Long, An Giang, and Hà. Tiên. In which, Đồng Tháp belonged to Vĩnh An district, Tân Thành district, Đông Xuyên district, Tuy Biên province (An Giang province) and Kiến Đăng district, Kiến An district (Định Tường province). Towards the end of King Tự Đức's reign, before the intervention of the French, today's Đồng Tháp land was mainly located in the districts of An Xuyên, Đông Xuyên, Vĩnh An (An Giang province) and Kiến Đăng and Kiến Phong district (Định Tường province).

Đồng Tháp during the French colonial period

Before the intervention of the French colonialists, Cochinchina consisted of 6 provinces: Biên Hòa, Gia Định, Định Tường (the Eastern) and An Giang, Vĩnh Long, Hà Tiên (the Western). In 1862, with the Treaty of Peace signed with the Huế court, the French colonialists occupied three eastern provinces and began to organize the ruling apparatus by abolishing the old districts under the Nguyễn dynasty and establishing new administrative units called the Inspection Area. In 1867, after continuing to occupy 03 western provinces (Vĩnh Long, An Giang and Hà Tiên), the French colonialists also placed these provinces under the same rule as the Eastern provinces.

In 1870, the entire Cochinchina had 25 inspection zones, by 1871 it was reduced to 18. In particular, the boundary of Đồng Tháp province today is located mainly in the Sa Đéc inspection area, including 03 districts: Vĩnh An, An Xuyên and Đông Xuyên. In 1876, the Sa Đéc inspection area was changed to the Sa Đéc district of the administrative district of Vĩnh Long - 01 of the four major administrative regions of Cochinchina. According to the Decree dated December 20th 1899 of the Governor General of Indochina, from January 1st 1900, the administrative regions in Cochinchina were unified as "provinces". At that time, Sa Đéc was one of the 20 provinces of Cochinchina.

In 1913, by Decree of Governor General of Indochina, Sa Đéc province was merged into Vĩnh Long province and established Cao Lãnh district. In 1916, Sa Đéc province was divided into 03 districts including Châu Thành (capital), Lai Vung and Cao Lãnh. In 1924, the Governor General of Indochina issued a Decree to separate Sa Đéc province from Vĩnh Long province into an independent province; at the same time, raising Cao Lanh administrative post to 01 administrative agency (Délégation administrative) in 1925.

Until August 1945, the administrative boundary of Đồng Tháp province was mainly located in Sa Đéc province, including 03 districts: Châu Thành, Lai Vung, Cao Lanh (south of Tiền river) and a part of provinces: Châu Đốc, Long Xuyên (North of Tiền river).

Đồng Tháp during 1945 – 1975

After the August Revolution in 1945, Sa Đéc province was belonged to War Zone 8 in the Central South region. On September 12th 1947, according to the Directive of the Southern Administrative Resistance Committee, Long Châu Tiền province was established on the basis of a part of Châu Đốc and Long Xuyên provinces including 05 districts: Tân Châu, Hồng Ngự, Chợ Mới, Châu Phú B and Lấp Vò. In 1950, Đồng Tháp Mười province was established from 29 communes of the districts: Cai Lậy, Cái Bè (Mỹ Tho province); Cao Lãnh (Sa Đéc province) and Mộc Hóa (Tân An province). In 1951, Long Châu Tiền province merged with Sa Đéc province to form Long Châu Sa province. Long Châu Sa province, which existed until 1954, was abolished to restore the provinces: Châu Đốc, Long Xuyên, Sa Đéc as before.

After the Geneva Agreement 1954, the country was temporarily divided into two regions, using the 17th parallel at Quảng Trị as the boundary line. The boundary from the 17th parallel to the South was under the management of the government of the Republic of Vietnam, Sa Đéc province at this time belonged to the Southwest part. In February of 1956, the Government of the Republic of Vietnam established Phong Thạnh province from a part of the provinces: Châu Đốc (Hồng Ngự district), Long Xuyên (Phong Thạnh Thượng district and An Binh canton), Sa Đéc (Cao Lanh district). In October 1956, the President of the Republic of Vietnam again issued the Decree on changing the boundaries and names of a number of provinces and provincial capitals in South Vietnam, whereby Sa Đéc province merged into Vĩnh Long into Vĩnh Long province. Phong Thạnh province changed its name to Kiến Phong province. In 1966, Sa Đéc province was re-established on the basis of separation from Vĩnh Long province.

Đồng Tháp after April 30th 1975 to present

On September 20th 1975, the Politburo of the Central Committee of the Vietnam Workers' Party issued Resolution No. 245-NQ/TW on the abolition of zones and provinces nationwide. According to this Resolution, it is expected to merge old provinces into 21 new provinces nationwide, of which 03 provinces: Long Châu Tiên, Sa Đéc, Kiến Tường are expected to merge into 01 new province. However, after considering the actual situation in the South, the Politburo decided to adjust the consolidation of some provinces from Zone 6 onwards, in which Sa Đéc province and the old Kiến Phong province were merged. On that basis, in February 1976, by the Decree of the Provisional Revolutionary Government of the Republic of South Vietnam, Đồng Tháp province was officially established from the merger of two provinces of Sa Đéc and Kiến Phong.

In 1976, when Đồng Tháp province was newly established, it had 01 Sa Đéc town (the provincial capital) and 05 districts: Cao Lãnh, Tam Nông, Hồng Ngự, Lấp Vò, Châu Thành with a total of 79 communes and 02 townships.

In 1994, in order to promote the development of Đồng Tháp Mười  area, the center of the province was moved to Cao Lãnh. With the investment of the Central Government, the efforts of the Party Committee, local authorities and people, Cao Lãnh town had been constantly developed and became a city directly under the province in 2007 and the second-class urban city in 2020.

Besides, Sa Đéc town became a city directly under the province in 2013 (class-II city in 2018); Hồng Ngự town was established in 2008 (class-III city in 2018) and has been become a city directly under the province since 2020.

Đồng Tháp is the first locality in the Mekong Delta region to have 03 cities directly under the province (currently, Kiên Giang province has achieved this).

(Translated by Gia Vi)