Jiaozhi (standard Chinese, pinyin: Jiāozhǐ, Vietnamese: Giao Chỉ), was a historical region ruled by various Chinese dynasties, corresponding to present-day northern Vietnam. The kingdom of Nanyue (204–111 BC) set up the Jiaozhi Commandery (; , chữ Hán: 郡交趾) an administrative division centered in the Red River Delta that existed through Vietnam's first and second periods of Chinese rule. During the Han dynasty, the commandery was part of a province of the same name (later renamed to Jiaozhou) that covered modern-day northern and central Vietnam as well as Guangdong and Guangxi in southern China. In 679 AD, Jiaozhi was absorbed into the Annan Protectorate established by the Tang dynasty. Afterwards, official use of the name Jiaozhi was superseded by "Annan" (Annam) and other names of Vietnam, except during the brief fourth period of Chinese rule when the Ming dynasty administered Vietnam as the Jiaozhi Province.

Name Chinese chroniclers assigned various folk etymologies for the toponym. In Book of Rites's subsection Royal Regulations, 交趾 was used to describe the physical characteristics of Nanman - southern neighbours of the Zhou. Late Eastern Han scholar Zheng Xuan (127 – c. 200 CE) interpreted 交趾 as "the appearance of feet turning in towards each other".禮記集說 (Collected Remarks on Book of Rites) Siku Quanshu version, "vols. 31–32", p. 127 of 160; quote: "交趾足相向然" 交趾 was subsequently translated as either "feet turned in towards each other" (James Legge)Liji, "Wangzhi" "南方曰蠻,雕題交趾,有不火食者矣。" James Legge's translation: "Those on the south were called Man. They tattooed their foreheads, and had their feet turned in towards each other. Some of them (also) ate their food without its being cooked." or "toes... crossed" (James M. Hargett)."The people in the southern quarter are called Man. Their foreheads are tattooed [diaoti] and their toes are crossed [jiaozhi]. And there are people among them who do not eat cooked food." quoted in James M. Hargett's 2010 translation of Fan Chengda's Treatises of the Supervisor and Guardian of the Cinnamon Sea. Publisher: University of Washington Press. Pp. 209–210 Book of Later Han also quoted the same passage from Book of Rites yet gave 交趾's etymology as: "[According to] their customs, men and women bathe in the same river; hence the appellation Jiāozhǐ".Book of Later Han, "Account of the Southern Man & Southwestern Yi" text: "禮記稱「南方曰蠻,雕題交阯」。其俗男女同川而浴,故曰交阯。" Compare Zheng Xuan's comment on the same Liji's passage; recorded in 禮記集說 (Collected Remarks on Book of Rites) Siku Quanshu version, "vols. 31–32", p. 127 of 160; quote: "浴則同川" Tang period's encyclopedia Tongdian also stated that: "The southernmost people [have] tattooed foreheads (題額) and intersecting toes (交趾); [according to] their customs, men and women bathe in the same river. [By] tattooed foreheads (題額) it means they engrave their flesh with blue/green dye; [by] crossed toes (交趾), it means that each foot's big toe is spread widely outwards and crosses one another when [a person] stands [with feet] side-by-side."Du You et al. Tongdian, vol. 188, quote: "極南之人雕題交趾 其俗男女同川而浴 題額也雕謂刻其肌肉用青湼之 交趾謂足大趾開闊並立相交 " Song period's encyclopaedia Taiping Yulan quoted Ying Shao's "Han Officials' Etiquettes" that "Emperor Xiaowu leveled the Hundred Yue in the South [...] established Jiaozhi (交阯); [...] [People] started out in the North, then crossed (交 jiāo) at the South, for their descendants [they laid their] basis (jī 基) & foundation (zhǐ 阯) [there]".Taiping Yulan, "3rd section on the Provinces & Prefectures: on the Provinces" txt: "應劭《漢官儀》曰:孝武皇帝南平百越,...,置交阯、... 始開北方,遂交南方,為子孫基阯也。"

A research based on historic record and petroglyph suggests the name Jiaozhi originated from Lingnan Yue people's ceremonial sitting posture of "sitting cross-legged" during sacrifices and other important occasions.

According to Michel Ferlus, the Sino-Vietnamese Jiao in Jiāozhǐ (交趾), together with the ethnonym and autonym of the Lao people (lǎo 獠), and the ethnonym Gēlǎo (仡佬), a Kra population scattered from Guizhou (China) to North Vietnam, would have emerged from *k(ə)ra:w. The etymon *k(ə)ra:w would have also yielded the ethnonym Keo/ Kæw kɛːwA1, a name given to the Vietnamese by Tai speaking peoples, currently slightly derogatory. In Pupeo (Kra branch), kew is used to name the Tay (Central Tai) of North Vietnam.

Frederic Pain proposes that *k(ə)ra:w means 'human being' and originates from Austroasiatic: he further links it to a local root *trawʔ, which is associated with taro, is ancestral to various Austroasiatic lexical items such as "Monic (Spoken Mon krao or Nyah-kur traw), Palaungic (Tung-wa kraɷʔ or Sem klao), or Katuic (Ong raw or Souei ʰraw < proto-Katuic *craw)", and possibly evoked "a particular (most probably tuber-based) cultivation practice used by small Mon-Khmer horticultural communities—as opposed to more complex and advanced cereal-growing (probably rice-based) societies"Frederic Pain. (2020) "”Giao Chỉ” (”Jiāozhǐ” ffff) as a diffusion center of Chinese diachronic changes: syllabic weight contrast and phonologisation of its phonetic correlates". halshs-02956831

Meanwhile, James Chamberlain claims that Jiao originated from a word also ancestral to Lao, thus meaning Jiao & Lao are cognates. Chamberlain, like Joachim Schlesinger, claim that the Vietnamese language was not originally based in the area of the Red River in what is now northern Vietnam. According to them, the Red River Delta region was originally inhabited by Tai-speakers. They claim that the area become Vietnamese-speaking only between the seventh and ninth centuries AD, or even as late as the tenth century, as a result of immigration from the south, i.e., modern north-central Vietnam. According to Han-Tang records, east of Jiaozhi and the coast of Guangdong, Guangxi was populated by Tai-Kadai speakers (whom Chinese contemporaries called Lǐ 俚 and Lǎo 獠). Catherine Churchman proposes that the Chinese character 獠 transliterated a native term and was shortened from older two-character combinations (which were used transcribe the endonym's initial consonantal cluster); noting that the older two-character combinations 鳩獠 Qiūlǎo, 狐獠 Húlǎo, and 屈獠 Qūlǎo had been pronounced *kɔ-lawʔ, *ɣɔ-lawʔ, and *kʰut-lawʔ respectively in Middle Chinese, she reconstructs the endonym *klao, which is either related to the word klao, meaning "person", in the Kra languages, or is a compound, meaning "our people", of prefix k- for "people" and Proto-Tai first person plural pronoun *rəu "we, us".Churchman, Catherine (2016) The People between the Rivers: The Rise and Fall of a Bronze Drum Culture, 200–750 CE. New York: Rowman & Littlefield. pp. 87–88 Even so, Michael Churchman acknowledged that "The absence of records of large-scale population shifts indicates that there was a fairly stable group of people in Jiaozhi throughout the Han–Tang period who spoke Austroasiatic languages ancestral to modern Vietnamese."

Jiaozhi, pronounced in the Malay, became the of the Portuguese traders , who so named it to distinguish it from the city and the Kingdom of Cochin in India, their first headquarters in the Malabar Coast. It was subsequently called "Cochinchina".

History Early mentions Numerous Chinese sources, dated to the Spring & Autumn and Warring States periods, mentioned a place called Jiao(zhi) to the south of Ancient China.Book of Documents "Canon of Yao" quote: "申命羲叔,宅南交。平秩南訛,敬致。" Legge's translation: "He further commanded the third brother Xi to reside at Nan-jiao, (in what was called the Brilliant Capital). to adjust and arrange the transformations of the summer, and respectfully-to observe the exact limit (of the shadow)."Records of ritual matters by Dai the Elder (大戴禮記) "A bit of leisure" text: "昔虞舜以天德嗣堯,布功散德制禮。朔方幽都來服;南撫交趾..." translation: "In former times, Shun of Yu used heavenly virtues when succeeding Yao. He deployed [public] work [projects], propagated virtues, and regulated propriety. In the North Youdu capitulated; in the South Jiaozhi was assuaged..."Mozi "Moderation in Use" A text: "古者堯治天下,南撫交阯 ..." translation: "In ancient times [Emperor] Yao governed all under Heaven, assuaging Jiaozhi in the South ..."Han Feizi "Ten Excesses" text: "由余對曰:「臣聞昔者堯有天下,... 其地南至交趾 ..." tr: "You Yu replied: 'I hear that in former times [Emperor] Yao held all under Heaven... His realm reached Jiaozhi in the South...'"Lüshi Chunqiu "Seeking People" text: "禹... 南至交阯、孫樸、續樠之國," translation: "Yu['s realm]..., in the South, reaches the Jiaozhi, Sunbu, Xuman nations..."Records of ritual matters by Dai the Elder (大戴禮記) "Five Emperors' Virtues" text: "孔子曰:「顓頊,... 乘龍而至四海:北至於幽陵,南至於交趾,西濟於流沙,東至於蟠木,..." translation: "Confucius said: 'Zhuanxu... when he died (lit. "rode the dragon"), [his realm] extended up to the Four Seas: reaching Youling in the North, reaching Jiaozhi in the South, fording the Flowing Sands in the West, reaching the Coiling Tree in the East,..."; text: "南撫交阯" translation: "(Confucius talking about Emperor Shun to Zai Yu): [Shun] assuaged Jiaozhi in the South" Book of Rites is the earliest extant source to associate the name Jiaozhi with the Nanman.Liji, "Wangzhi" "南方曰蠻,雕題交趾,有不火食者矣。" However, Vietnamese historian Đào Duy Anh locates Jiaozhi (which was mentioned in ancient texts) only south of Mount Heng (衡山) (aka 霍山 Mount Huo or 天柱山 Mount Tianzhu), within the lower part of Yangtze's drainage basin, and nowhere farther than today Anhui province in China (i.e. not in today northern Vietnam); accordingly, Đào defines Jiao(zhi) as "lands in the south which bordered [ancient Chinese's] territories".Đào Duy Anh, "Jiaozhi in Shujing", excerpts from Đào's 2005 book Lịch Sử Cổ Đại Việt Nam. Hanoi : Culture & Information Publisher.

Van Lang

The native state of Văn Lang is not well attested, but much later sources name as one of the realm's districts (). Its territory purportedly comprised present-day Hanoi and the land on the right bank of the Red River. According to tradition, the Hung kings directly ruled Mê Linh while other areas were ruled by dependent Lac lords. The Van Lang kingdom fell to the Âu under prince Thục Phán around 258 BC.

Âu Lạc

Thục Phán established his capital at Co Loa in Hanoi's Dong Anh district. The citadel was taken around 208 BC by the Qin general Zhao Tuo.

Nanyue

Zhao Tuo declared his independent kingdom of Nanyue in 204 and organized his Vietnamese territory as the two commanderies of Jiaozhi and Jiuzhen (; present-day Thanh Hóa, Nghệ An, and Hà Tĩnh). Following a native coup that killed the Zhao king and his Chinese mother, the Han launched two invasions in 112 and 111 BC that razed the Nanyue capital at Panyu (Guangzhou). When Han dynasty conquered Nanyue in 111 BC, the Han court divided it into 9 commanderies, one commandery called Jiaozhi was the center of Han administration and government for all 9 areas. Because of this, the entire areas of 9 commanderies was sometime called Jiaozhi. From Han to Tang, the names Jiaozhi and Jiao county at least was used for a part of the Han-era Jiaozhi. In 670, Jiaozhi was absorbed into a larger administrative called Annan (Pacified South). After this, the name Jiaozhi was applied for the Red River Delta and most or all of northern Vietnam (Tonkin).Zhao Rukuo, 46, n. 1. As cited in

Han dynasty

The Han dynasty received the submission of the Nanyue commanders in Jiaozhi and Jiuzhen, confirming them in their posts and ushering in the "First Era of Northern Domination" in Vietnamese history. These commanderies were headed by grand administrators (taishou) who were later overseen by the inspectors (, cishi) of Jiaozhou or (), the first of whom was Shi Dai.