Tamna, or Tamna-guk, was a state based on Jeju Island from ancient times until it was absorbed by the Korean Joseon dynasty in 1404, following a long period of being a tributary state or autonomous administrative region of various Korean kingdoms. The Go (Jeju) clan is the family name of the Grand Duke (Seongju, 성주, 星主), that ruled West Tamna over 400 years. The Moon (Nampyeong) clan is the family name of the Grand Prince (Wangja, 왕자, 王子), that ruled East Tamna for 400 years. The Kingdom of Tamna is also sometimes known as Tangna (탕나), Seomna (섬나), and Tammora. All of these names mean "island country". Legends of founding There is no discovered historical record of the founding or early history of Tamna. One legend tells that the three divine founders of the country—Go (고), Yang (양), and Bu (부)—emerged from three holes in the ground in the 24th century BC. These holes, known as the Samseonghyeol (삼성혈), are still preserved in Jeju City. According to legend, after Yang Eulna (양을나/楊乙那) came to Jeju Island, a semi-mythical box washed up on the shore of the island. Yang Ul-la searched in the box and found three women, horses, cows, and agricultural seeds such as rice, corn, grain, millet, barley, and bamboo. From these beginnings, the three men established the kingdom of Tamna. He is regarded as the legendary ancestor of Yang Tang, the founder of the Jeju Yang bon-gwan. Historical and archaeological records Archaeological evidence indicates that the people of Tamna were engaging in active trade with Han China and Yayoi Japan, South-east-Asian nations, with the Tamil Chola dynasty, as well as Korea, by the 1st century AD. The first historical reference to the kingdom may come in the 3rd century AD, in the chronicle of the Chinese Three Kingdoms period called the Sanguozhi. The Sanguozhi reports a strange people living on a large island near Korea, which it calls Juho (州胡, Late Han Chinese tɕu-ga, literally "island barbarians"). These people, who had a distinctive language and culture, engaged in trade with the Mahan people of the mainland. However, the identity of Juho with Tamna has been disputed by authorities such as the North Korean scholar Lee Ch'i-rin (이지린), who claims that Juho was a small island in the Yellow Sea. Tamna is pronounced Dānluó (Wade-Giles: Tan1-luo2) in Standard Mandarin Chinese. In 476, according to the Samguk Sagi, Tamna entered