Northern Vietnam in the context of Northeast (Vietnam)

The Red River Delta or Hong River Delta (Vietnamese: Đồng bằng sông Hồng) is the flat low-lying plain formed by the Red River and its distributaries merging with the Thái Bình River in Northern Vietnam. Hồng (紅) is a Sino-Vietnamese word for "red" or "crimson". The delta has the smallest area but highest population and population density of all regions in Vietnam. The region, measuring some 15,000 square kilometres (6,000 sq mi) is well protected by a network of dikes. It is an agriculturally rich and densely populated area. Most of the land is devoted to rice cultivation.

Eight provinces, together with two municipalities (the capital Hanoi, and the port of Haiphong) form the delta. It had a population of almost 23 million in 2019.

Emperor Wu of Han (156 – 29 March 87 BC), personal name Liu Che and courtesy name Tong, was the seventh emperor of the Han dynasty from 141 to 87 BC. His reign lasted 54 years – a record not broken until the reign of the Kangxi Emperor more than 1,800 years later – and remains the record for ethnic Han emperors. His reign resulted in a vast expansion of geopolitical influence for the Chinese civilization, and the development of a strong centralized state via governmental policies, economical reorganization and promotion of a hybrid Legalist–Confucian doctrine. In the field of historical social and cultural studies, Emperor Wu is known for his religious innovations and patronage of the poetic and musical arts, including the development of the Imperial Music Bureau into a prestigious entity. It was also during his reign that cultural contact with western Eurasia was greatly increased, directly and indirectly.

During his reign, Emperor Wu led the Han dynasty through its greatest territorial expansion. At its height, the Empire's borders spanned from the Fergana Valley in the west, to northern Korea in the east, and to northern Vietnam in the south. Emperor Wu successfully repelled the nomadic Xiongnu from systematically raiding northern China, and dispatched his envoy Zhang Qian into the Western Regions in 139 BC to seek an alliance with the Greater Yuezhi and Kangju, which resulted in further diplomatic missions to Central Asia. Although historical records do not describe him as being aware of Buddhism, emphasizing rather his interest in shamanism, the cultural exchanges that occurred as a consequence of these embassies suggest that he received Buddhist statues from Central Asia, as depicted in the murals found in the Mogao Caves.

Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of Mainland Southeast Asia. With an area of about 331,000 square kilometres (128,000 sq mi) and a population of over 100 million, it is the world's 15th-most populous country. One of two communist states in Southeast Asia, Vietnam is bordered by China to the north, Laos and Cambodia to the west, the Gulf of Thailand to the southwest, and the South China Sea to the east; it also shares maritime borders with Thailand, Malaysia, and Indonesia to the south and southwest, the Philippines to the east, and China to the northeast. Its capital is Hanoi, while its largest city is Ho Chi Minh City.

Vietnam was inhabited by the Paleolithic age, with states established in the first millennium BC on the Red River Delta in modern-day northern Vietnam. The Han dynasty annexed northern and central Vietnam, which were subsequently under Chinese rule from 111 BC until the first dynasty emerged in 939. Successive monarchical dynasties absorbed Chinese influences through Confucianism and Buddhism, and expanded southward to the Mekong Delta, conquering Champa. During most of the 17th and 18th centuries, Vietnam was effectively divided into two domains of Đàng Trong and Đàng Ngoài. The Nguyễn—the last imperial dynasty—surrendered to France in 1883. In 1887, its territory was integrated into French Indochina as three separate regions. In the immediate aftermath of World War II, the Viet Minh, a coalition front led by the communist revolutionary Ho Chi Minh, launched the August Revolution and declared Vietnam's independence from the Empire of Japan in 1945.

The Vietnamese government often groups the various provinces and municipalities into three regions: Northern Vietnam, Central Vietnam, and Southern Vietnam. These regions can be further subdivided into eight subregions: Northeast Vietnam, Northwest Vietnam, the Red River Delta, the North Central Coast, the South Central Coast, the Central Highlands, Southeast Vietnam, and the Mekong River Delta. These regions are not always used, and alternative classifications are possible. Other classifications used can be: Northern, Central, Southern, and Mekong.

The Vietnamese people (Vietnamese: người Việt, lit. 'Việt people') or the Kinh people (Vietnamese: người Kinh, lit. 'Metropolitan people'), also known as the Viet people or the Viets, are a Southeast Asian ethnic group native to modern-day northern Vietnam and southern China who speak Vietnamese, the most widely spoken Austroasiatic language.

Vietnamese Kinh people account for 85.32% of the population of Vietnam in the 2019 census, and are officially designated and recognized as the Kinh people (người Kinh) to distinguish them from the other minority groups residing in the country such as the Hmong, Cham, or Mường. The Vietnamese are one of the four main groups of Vietic speakers in Vietnam, the others being the Mường, Thổ, and Chứt people. Diasporic descendants of the Vietnamese in China, known as the Gin people, are one of 56 ethnic groups officially recognized by the People's Republic of China, residing in the Guangxi Zhuang Autonomous Region.

The Gulf of Tonkin is a gulf at the northwestern portion of the South China Sea, located off the coasts of Tonkin (northern Vietnam) and South China. It has a total surface area of 126,250 km (48,750 sq mi). It is defined in the west and northwest by the northern coastline of Vietnam down to the Cồn Cỏ island, in the north by China's Guangxi Zhuang Autonomous Region, and to the east by the Leizhou Peninsula and Hainan Island.

English sources from the People's Republic of China refer to the Gulf of Tonkin as Beibu Wan.

The Baiyue, Hundred Yue, or simply Yue, were various ethnic groups who inhabited the regions of southern China and northern Vietnam during the 1st millennium BC and 1st millennium AD. They were known for their short hair, body tattoos, fine swords, and naval prowess.

During the Warring States period, the word "Yue" referred to the state of Yue in Zhejiang. The later kingdoms of Minyue in Fujian and Nanyue in Guangdong were both considered Yue states. During the Zhou and Han dynasties, the Yue lived in a vast territory from Jiangsu to Yunnan, while Barlow (1997:2) indicates that the Luoyue occupied the southwest Guangxi and northern Vietnam. The Book of Han describes the various Yue tribes and peoples can be found from the regions of Kuaiji to Jiaozhi.

Tonkin (chữ Hán: 東京), or Bắc Kỳ (北圻), was a French protectorate encompassing modern Northern Vietnam from 1883 to 1949. Like the French protectorate of Annam, Tonkin was still nominally ruled by the Vietnamese Nguyễn dynasty. In 1886, the French separated Tonkin from the Nguyễn imperial court in Huế by establishing the office of "Viceroy" (經略衙, Kinh lược nha). However, on 26 July 1897, the position of Viceroy was abolished, officially making the French resident-superior of Tonkin both the representative of the French colonial administration and the Nguyễn dynasty court in Huế, giving him the power to appoint local mandarins. In 1887, Tonkin became a part of the Union of Indochina.

In March 1945, the emperor Bảo Đại rescinded the Patenôtre Treaty, ending the French protectorates over Annam and Tonkin, establishing the Empire of Vietnam, a Japanese-backed state. Following the surrender of Japan, ending World War II, the Việt Minh launched the August Revolution which led to the abdication of Bảo Đại and the declaration of independence of the Democratic Republic of Vietnam.

Vietnam under Chinese rule or Bắc thuộc (北屬 lit. "belonging to the north") (111 BCE–939 CE, 1407–1428 CE) refers to four historical periods during which several portions of modern-day northern and central Vietnam were governed by successive Chinese dynasties. Vietnamese historiography traditionally dates the beginning of this period to 111 BCE, when the Han dynasty annexed Nanyue (Vietnamese: Nam Việt). Chinese control continued in various forms until 939 CE, when the Ngô dynasty was established, marking the end of what is usually referred to as the main phase of Chinese rule. A later period of occupation by the Ming dynasty from 1407 to 1428 is often treated as a distinct episode. Notably, parts of Vietnam were under Chinese rule for longer than several territories that now form the modern provinces of China, underlining the longevity and depth of Chinese influence in the region over many centuries.

The historiography of this period has become a subject of scholarly debate, particularly concerning how national and cultural identities have been retroactively applied. Historians such as Catherine Churchman, Jaymin Kim, and Keith W. Taylor argue that many narratives about Bắc thuộc are shaped by modern constructs, often influenced by nationalist or anti-colonial sentiment. These scholars emphasise that the idea of an unbroken narrative of resistance or subjugation simplifies a more complex historical relationship, which included periods of accommodation, syncretism and local autonomy. Recent research critiques the use of this history as a tool for contemporary nationalist and irredentist projects in Vietnam, China and elsewhere.

The Ngô dynasty (Vietnamese: Nhà Ngô; Chữ Nôm: 茹吳), officially Tĩnh Hải quân (chữ Hán: 靜海軍), was a semi-independent Vietnamese dynasty from 939 to 968. The dynasty was founded by Ngô Quyền, who led the Vietnamese forces in the Battle of Bạch Đằng River against the Chinese Southern Han dynasty in 938.

Around 930, as Ngô Quyền rose to power, northern Vietnam was militarily occupied by the Southern Han and was treated as an autonomous province and vassal state of the Later Tang Dynasty, referred to as Tĩnh Hải quân. Every year the Jiedushi of Tĩnh Hải quân had to pay tribute to its Chinese master in exchange for peace and political support. At the beginning of the 10th century, China was domestically plagued and weakened by civil war during what is known as the Five Dynasties and Ten Kingdoms period. The Chinese were preoccupied with these civil struggles and lost their grip on Tĩnh Hải quân periodically. Tĩnh Hải quân took advantage of this opportunity and proclaimed its independence and seceded from China. Under the rule of Lord Protector Dương Đình Nghệ, the Tĩnh Hải quân state initiated a full blown military campaign for independence.

Tonkin, also spelled Tongkin, Tonquin or Tongking, is an exonym referring to the area surrounding the Red River Delta of Northern Vietnam. During the 17th and 18th centuries, this term referred to the domain of Đàng Ngoài, under the control of the Trịnh lords, encompassing both the Northern and Thanh–Nghệ regions, north of the Gianh River at the 17.7th parallel. From 1884 to early 1945, the term referred to the French protectorate of Tonkin, which comprised only the Northern region, approximately north of the 20th parallel.

Southern Vietnam (Vietnamese: Nam Bộ) is one of the three geographical regions of Vietnam, the other two being Northern and Central Vietnam. It includes 2 administrative subregions, which in turn are divided into 19 First Tier units, of which 17 are provinces and 2 are municipalities.

Known as Nam Bộ today in Vietnamese, it was historically called Gia Định (1779–1832), Nam Kỳ (1832–1945, during Nguyễn's Lục tỉnh and French Cochinchina), Nam Bộ (1945 to the present, encompassing the Empire of Vietnam and the Democratic Republic of Vietnam), and Nam Phần, sometimes Nam Việt (1948–1975, during the State of Vietnam and the Republic of Vietnam). Cochinchina is a historical exonym for this region during the colonial period, which referred to the entire domain of Đàng Trong in the feudal period. A more accurate term for the southern region is Lower Cochinchina, or Basse-Cochinchine in French.

The Trưng sisters, known in Vietnamese as Hai Bà Trưng (Vietnamese pronunciation: [haj ɓa t͡ɕɯŋ], 𠄩婆徵, "Two Ladies [named] Trưng") or simply Hai Bà ("The Two Ladies"), c.14 – c. 43) were Lac Viet military leaders who ruled for three years after commanding a rebellion of Lac Viet tribes and other tribes in AD 40 against the first Chinese domination of Vietnam. They are regarded as national heroines of Vietnam. Their names were Trưng Trắc and Trưng Nhị. Trưng Trắc was the first female monarch in Vietnam, as well as the first queen in the history of Vietnam (Lý Chiêu Hoàng was the last woman to take the reign and is the only empress regnant), and she was accorded the title Queen Trưng in the Đại Việt sử ký toàn thư.

The sisters were born in Jiaozhi (Giao Chỉ), a commandery of the Chinese Han dynasty in modern-day northern Vietnam. The dates of their births are unknown, but Trưng Trắc was older than Trưng Nhị. The exact dates of their deaths are also unknown but both died around 43 AD after battling against the punitive expedition force led by Eastern Han general Ma Yuan.

The Trưng sisters' rebellion was an uprising in the Jiaozhi province of Han dynasty (today Northern Vietnam) between 40 CE and 43 CE. In 40 CE, the Lạc Việt leader Trưng Trắc and her sister Trưng Nhị rebelled against Chinese authorities. In 42 CE, Han China dispatched General Ma Yuan to lead an army to strike down the uprising. In 43 CE, the Han army fully suppressed the uprising and regained complete control. The Trưng sisters were captured and beheaded by the Han forces, although Vietnamese chronicles of the defeat record that the two sisters, having lost to Han forces, decided to commit suicide by jumping down the Hát Giang river, so as not to surrender to the Han.

The Military of the Nguyễn dynasty (Vietnamese: Quân thứ; chữ Hán: 軍次) were the main military forces of the Nguyễn dynasty from 1802 to August 1945 when it was dismantled by the August Revolution. The Nguyễn military force was initially formed by Nguyễn Hoàng as a division of the military of the Revival Lê dynasty in 1558 starting out with 3000 soldiers. During this period it was the military forces of the domain of the Nguyễn lords and commonly fought the Trịnh lords who controlled northern Vietnam. During the Tây Sơn Rebellion it was expelled out most of the county by the Tây Sơn dynasty. After the exiled Nguyễn Phúc Ánh returned and defeated the Tây Sơn rebels he crowned himself as the Gia Long Emperor and the Nguyễn military became the national military of Vietnam.

During the French domination period it became two of the five indigenous guards of French Indochina and was turned into a collection police and ceremonial forces. While the Emperor was still nominally the supreme commander actual power fell in the hands of the French administration relegating the Emperor to a rubber stamp office. Following the abolition of the Nguyễn dynasty its military was also disbanded making the Vietnamese People's Army the new national military of Vietnam, which would be administered by the newly established Democratic Republic of Vietnam.