Map - Cao Bang province (Tỉnh Cao Bằng)

Cao Bằng is a province of the Northeast region of Vietnam. The province has borders with Hà Giang, Tuyên Quang, Bắc Kạn, and Lạng Sơn provinces within Vietnam. It also has a common international border with Guangxi province in China. The province covers 6,724.6 square kilometres, and, as of 2019, its population was 530,341 people.

The area has a rich history tracing to the Bronze Age Tây Âu (西甌) Kingdom of the ethnic Tày. Cao Bằng has several points of historical interest as well as many natural features such as the Pác Bó (at the mouth of the confluence of two rivers, the Bằng Giang and Hien rivers) where Hồ Chí Minh in January 1941 established a revolutionary force at Cốc Bó cave, the Mạc emperor's Temple, the Kỳ Sầm Temple, Coi Bin Church, the Bản Giốc waterfall area at the international border between Vietnam and China, and the Thang Hen Mountain Lake.

Cao Bằng's history can be traced to the Bronze Age when the Tày Tây Âu Kingdom flourished. The Tây Âu or Âu Việt were a conglomeration of upland Tai tribes living in what is today the mountainous region of northernmost Vietnam, western Guangdong, and southern Guangxi, China, since at least the 3rd century BC. According to local lore, the capital was located near today Cao Bằng City. In the 3rd century BC, the Tây Âu leader Thục Phán shifted their capital to Cổ Loa in the Red River Delta.

Cao Bằng's proximity to China has meant that it has had a somewhat turbulent history, having changed hands a number of times. What are now the provinces of Cao Bằng and Lạng Sơn were known as châu Quảng Nguyên during the time of the Lý and Trần Dynasties. Quảng Nguyên became part of Đại Việt in 1039, when Emperor Lý Thái Tông expelled Nùng Trí Cao, a Tày-Nùng leader, from the area.

At the end of the 14th century, Tày lords dynasties ruled the area, such as Bế Khắc Thiệu and Nga Dac Thai. In the 1430s, the Lê Dynasty had many rebellions. Royalty faced strong revolt during the 16th and early part of the 17th century – Mạc Đăng Dung initially occupied the territory and the Lê throne in 1527. However, the Lê kings were reinstated in 1592. Still, the war for control of the region continued and the Mạc family had the upper hand as they declared it an independent region and ruled for 75 years. As witness to this period, here lie ruins of a temple, which was also the palace of the Mạc Kings. It can be seen in the town of Cao Bình, which is located about 12 km north of the town of Cao Bằng. Cao Bình was a prominent administrative town until the French occupied the territory; the capital was shifted to the Cao Bằng peninsula when the French conquered the area in 1884. They fortified the town with a fort on a hill overlooking the town (ruins of this fort are seen even now). This fort area is now a high-security zone of the People’s Army of Vietnam.

Cao Bằng has a long history of revolutionaries and nationalists. The significant history of the peninsula to the present regime is recorded from the 1920s when it became the "cradle of the revolutionary movement in the north". Many pro-independence groups based themselves in the mountains. The Communist Party of Vietnam chose the province as a base, using the rough terrain as protection. Its historicity was further accentuated when Hồ Chí Minh, on his return from China in exile in 1941, made his headquarters at Pắc Bó, in Trường Hà commune, Hà Quảng District, 56 km north of Cao Bằng for the decisive revolutionary movement between 1940 and 1945.

In 1950, the province had 10 districts: Bảo Lạc, Hạ Lang, Hòa An, Nguyên Bình, Phú Thạch, Phục Hòa, Quảng Uyên, Thạch An, Trấn Biên and Trùng Khánh. In 1958, Trấn Biên was renamed Trà Lĩnh. The district of Thông Nông was created out of part of the district of Hà Quảng by Decision 67-CP on 7 April 1966. The districts of Phục Hòa and Quảng Uyên were merged to become Quảng Hòa by Decision 27-CP on 8 March 1967. The district of Hạ Lang was abolished and integrated into the districts of Quảng Hòa and Trùng Khánh by Decision 176-CP on 15 September 1969.

In December 1978, the two districts of Ngân Sơn and Chợ Rã were transferred from the province of Bắc Thái to Cao Bằng by a decree of the congress of the Communist Party. This meant that Cao Bằng had 11 districts: Bảo Lạc, Hà Quảng, Hòa An, Nguyên Bình, Quảng Hòa, Thạch An, Thông Nông, Trà Lĩnh, Trùng Khánh, Ngân Sơn and Chợ Rã. The district of Chợ Rã was renamed Ba Bể by Decision 144-HĐBT on 6 November 1984.

On 27 February 1979, during the Sino-Vietnamese War, Chinese troops entered and occupied the city of Cao Bằng, inflicting a "scorched earth" policy by levelling most of the city, including places of worship. The historical areas near the Pác Bó caves in the commune of Trường Hà in Hà Quảng district were mined and bombed, demolishing most of the cave mouth where Hồ Chí Minh based his guerrilla activities in the 1940s and 1950s. In 1996, the districts of Ngân Sơn and Ba Bể were transferred into the newly created province of Bắc Kạn. The district of Bảo Lâm was created by carving out a portion of Bảo Lạc District, in accordance with Decree 52/2000/NĐ-CP on 25 September 2000.