Chinese texts from the Han dynasty (206 BCE – 220 CE) onwards claimed that King Wu enfeoffed Jizi as ruler of Chaoxian (朝鮮, pronounced "Joseon" in Korean).

According to the Book of Han (1st century CE), Jizi brought agriculture, sericulture, and many other facets of Chinese civilization to Joseon.

Starting in the late thirteenth century, Gija was fully integrated into Korean history, being described as a successor to the descendants of Dangun in the state of Old Joseon.

However, with the development of radiocarbon dating and newly found excavations, modern Korean historians started to question the legitimacy of his enfeoffment as ruler of Gojoseon.

In recent times, both North and South Korea, and their respective historians do not officially recognize Jizi and his supposed accomplishments,[4] making China the only nation that still supports his claims.

)[7] After Shang was overthrown by the Zhou dynasty in the mid eleventh century BC, Jizi was released by King Wu, to whom he gave advice on how to rule the new polity.

[8] The earliest known source stating that Jizi went to Joseon is the Shangshu dazhuan (尚書大傳), a commentary on the Book of Documents attributed to Fu Sheng of the second century BC.

The "Monograph on Geography" (Dili zhi 地理志) of the Book of Han (1st century AD) claims that Jizi had taught the people of Joseon agriculture, sericulture, and weaving, as well as proper ceremony.

[10] Jae-hoon Shim interprets the following sentence in that section of the Hanshu as claiming that Jizi also introduced the law of "Eight Prohibitions" (犯禁八條) in Joseon.

[18] Shin Chaeho (1880–1936), a Korean independence nationalistic activist historian during the Japanese occupation, was the first to question the extent of Gija's contributions.

[3] In addition, Ri Chirin, a leading North Korean historian of ancient Korea, argued that the Gija legend had been forged in Han times when the Chinese started to occupy part of Joseon.

In addition, detractors of the Gija Joseon theory also point out that the cultural artifacts found in the region do not appear to have Chinese origins.

[4] Additionally, the 7th edition of the Korean textbooks do not mention Jizi/Gija, making China the only nation to officially support the preceding theory.