Candrapuri

A reference to the name Vientiane can be seen on a Vietnamese inscription of Duke Đỗ Anh Vũ, dated 1159 during the Khmer-Viet conflict. The inscription says that in 1135, Văn Đan (Vientiane), a vassal of Zhenla (Khmer Empire), invaded Nghe An, and was repelled by the Duke; the Duke led an army chased the invaders as far as Vũ Ôn? (unattested), and then returned with captives.^[6]: 65

A few decades later, Phraya Chanthaburi (lit. 'King of Chanthaburi'; Vientiane), together with his elder brother Tao Gwa (ท้าวกวา) of Mueang Kaew (Kao) Prakan (เมืองแกว(กาว)ประกัน; lit. 'the Viet or Tai Kao [th] city of Prakan'^[2]: 262)—a polity commonly identified with Xiangkhouang (Muang Phuan)^[7]—launched a large-scale military invasion of the Ngoenyang Kingdom of the Tai Yuan in 1150s. The invasion failed, however, as the Ngoenyang ruler Khun Chin sought military assistance from his nephews, the Chueang brothers. After successfully expelling the invaders, the younger Chueang marched eastward, annexed several polities, and eventually captured Muang Phuan.^{[8]: 9 [1]: 76–9} He then appointed his middle son, also named Chueang, as ruler of Muang Phuan, and his youngest son, Lao Pao (ลาวพาว), as ruler of Vientiane.^{[1]: 82–3}

As another Laotian city-kingdom, the northern neighbor Muang Sua experienced a brief period of Angkorian suzerainty under Jayavarman VII from 1185 to 1191;^[9]: 33 on this basis, Candrapuri, located between these two polities, may tentatively be understood as having experienced similar Angkorian influence. This interpretation is supported by the establishment of the Sanskrit–Lao Say Fong Inscription of Jayavarman VII K.368, dated to 1186, in the Vientiane area.^[10]

However, the aforementioned presupposition has been challenged. No archaeological evidence of 12th century Bayon-style Angkorian architecture has been identified in the area, despite the inscription’s statement that Jayavarman VII ordered the construction of an ārogyasālā (hospital). Michel Lorrillard has argued that the inscription may have been relocated from Khu Ban Phanna (กู่บ้านพันนา; lit. 'Ban Phanna Shrine') in the modern Sawang Daen Din District of Thailand—currently the northernmost known area with Angkorian architectural remains—possibly during the French colonial period, when cultural heritage was used to justify territorial claims and administrative control.^[10] Lorrillard’s hypothesis is consistent with the findings of Anna Karlström’s 2009 survey.^[11]

In the 13th century, during the reign of Ramkhamhaeng, Candrapuri or Vientiane was named as one of the polities under the Sukhothai Kingdom.^[12] However, later scholarship suggests that Sukhothai may not have exercised direct control over Vientiane; rather, the relationship likely reflected a mandala-style political arrangement based on dynastic connections.^[13] Vientiane continued to function as an autonomous city-kingdom until it was annexed in 1356 by Fa Ngum during his campaign to unite the Lao muangs into a single kingdom, Lan Xang.^[5]