Since the 10th century, Ubon Ratchathani , or simply Ubon, was part of the Khmer Empire until the Ayutthaya Kingdom later conquered it. Towards the end of the 18th century, Laotians immigrated to the northern banks of the Mun River and founded the provincial capital. The Laotian influence is evident in the architectural structures of some of the city's religious buildings. During the Vietnam War, Ubon encountered an expansive growth due to its proximity to an American air base.

         Today, the province is the largest and one of the most important provinces in northeastern Thailand . It is a major tourist attraction of the lower I-San located 629 kilometres from Bangkok . Due to the large number of fascinating temples dotting the city, Ubon is a place of pilgrimage at the beginning of Buddhist Lent. Aside from the numerous attraction sites, festivals and holidays are celebrated with a unique Ubon flair. The province borders the Mekong River in the east and features superb scenic view of Cambodia .

         The province covers 15,517 square kilometres and is divided into the following districts: Muang, Warin Chamrap, Det Udom, Buntharik, Na Chaluai, Nam Yuen, Phibun Mangsahan, Khong Chiam, Si Muang Mai, Trakan Phuet Phon, Khemarat, Mung Sam Sip, Khueang Nai, Kut Khaopun, Tan Sum, Pho Sai, Samrong, Sirindhorn, Don Mot Daeng, Thung Si Udom, Na Yia, Na Tan, Lao Suea Kok, Sawang Wirawong and Nam Khun .

Reference : Tourism Authority of Thailand