Tonkin, historic region (c.40,000 sq mi/103,600 sq km), SE Asia, now forming the heartland of N Vietnam. The capital was Hanoi. Tonkin was bordered on the north by China, on the east by the Gulf of Tonkin, on the south by the historic region of Annam, and on the S and W by Laos. The region of Tonkin was conquered in 111 B.C. by the Chinese, who ruled until they were ousted in A.D. 939, at which time the area became independent. The inhabitants began a southward expansion, and by 1471 they had acquired the kingdom of Champa. After the division of the Vietnamese lands between two dynasties in 1558, the northern half was ruled from the city of Tonkin (modern Hanoi); thus the name of Tonkin came to be applied by Europeans to the whole area. The two regions were reunited in 1802 under the rule of the restored line of Hue as part of the empire of Vietnam. To open the Red River to French trade, French expeditions were sent into Tonkin in 1873 and 1882; that of 1882 resulted in a full-scale colonial war, complicated by Chinese intervention (China also claimed the region) against the French. In 1884, Annam accepted a French protectorate, conceding France a separate protectorate over Tonkin with control more direct than over Annam. In 1887, Tonkin became part of the Union of Indochina. In World War II, the region was occupied (1940-45) by the Japanese. After the war Tonkinese and Annamese nationalist leaders joined in demanding independence for the state of Vietnam, and Tonkin was torn by guerrilla warfare between the French and the Viet Minh nationalists led by Ho Chih Minh. The name also appears as Tongking and Tonking.

Tonkin, Gulf of, NW arm of the South China Sea, c.300 mi (480 km) long and 150 mi (240 km) wide, between Vietnam and China. The shallow gulf (less than 200 ft/60 m deep) receives the Red River. Haiphong, Vietnam, and Peihai (Pakhoi), China, are the chief ports. An alleged attack (Aug., 1964) by North Vietnamese gunboats against U.S. naval forces stationed in the gulf led to increased U.S. involvement in the Vietnam War (see Tonkin Gulf Resolution).

Arm of the South China Sea, between northern Vietnam and Hainan Island, China. It is 300 mi (500 km) long and 150 mi (250 km) wide. In 1964 the Vietnamese reportedly fired on U.S. ships there, leading the U.S. Congress to adopt the Gulf of Tonkin Resolution that supported increased U.S. involvement in the Vietnam War.

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Former French protectorate, mainland Southeast Asia, now constituting the greater part of northern Vietnam. It was part of China from the 2nd century BC until the Vietnamese won independence in the 10th century AD. The French seized the area in 1883, making it a protectorate; it was joined with other regions controlled by France in 1887 to form French Indochina. It was the chief focus in the area of anti-French fighting after World War II.

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Arm of the South China Sea, between northern Vietnam and Hainan Island, China. It is 300 mi (500 km) long and 150 mi (250 km) wide. In 1964 the Vietnamese reportedly fired on U.S. ships there, leading the U.S. Congress to adopt the Gulf of Tonkin Resolution that supported increased U.S. involvement in the Vietnam War.

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Tonkin (Đông Kinh in Vietnamese), also spelled Tongkin, Tonquin or Tongking, is the northernmost part of Vietnam, south of China's Yunnan and Guangxi Provinces, east of northern Laos, and west of the Gulf of Tonkin. Locally, it is known as Bắc Kỳ, meaning "Northern Region". Located on the fertile delta of the Red River, Tonkin is rich in rice production.

The term derives from Đông Kinh (東京), a former name of Hanoi, which was the capital of Vietnam since the 7th century. (The name means "eastern capital", and is identical in meaning and written form in Chinese characters to that of Tokyo.)

History

The area was called Van Lang by Vietnamese ancestors at around 2000-100 BCE. Evidence of the earliest established society other than the Đông Sơn culture in Northern Vietnam was found in Cổ Loa, the ancient city situated near present-day Hà Nội. According to Vietnamese myths the first Vietnamese peoples descended from the Dragon Lord Lạc Long Quân and the Immortal Fairy Âu Cơ. Lạc Long Quân and Âu Cơ had 100 sons before they decided to part ways. 50 of the children went with their mother to the mountains, and the other 50 went with their father to the sea. The eldest son became the first in a line of earliest Vietnamese kings, collectively known as the Hùng kings (Hùng Vương or the Hồng Bàng Dynasty). The Hùng kings called the country, which was then located on the Red River delta in present-day northern Vietnam, Văn Lang. The people of Văn Lang were referred to as the Lạc Việt.

Tonkin (French colony)

France assumed sovereignty over all of Vietnam after the Sino-French War (1884-1885). The French colonial government then divided Vietnam into three different administrative territories. They named the territories: Tonkin (in the north), Annam (in the center), and Cochinchina (in the south). These territories were fairly arbitrary in their geographic extent. The vast majority of the Vietnamese regarded their country as a single land and fought for much of the next 90 years to achieve unification.