Mahan (Korean pronunciation: [ma.?an]) was a loose confederacy of statelets that existed from around the 1st century BC to 5th century AD in the southern Korean peninsula in the Chungcheong and Jeolla provinces. Arising out of the confluence of Gojoseon migration and the Jin state federation, Mahan was one of the Samhan ("Three Hans"), along with Byeonhan and Jinhan. Baekje began as a member statelet, but later overtook all of Mahan and became one of the Three Kingdoms of Korea.
Mahan probably developed from the existing bronze society of third to second centuries BC, continuing to absorb migration from the north in subsequent centuries. King Jun of the kingdom of Gojoseon in northern Korea, having lost the throne to Wiman, fled to the state of Jin state in southern Korea around 194 - 180 BC. He and his followers are thought to have established a base within Jin territory. It is not certain whether Mahan conquered or arose out of this entity, but Mahan was certainly influenced by this influx of northern culture.
Further migration followed the fall of Gojoseon and establishment of the Chinese commanderies in the Liaoning region in 108 BC. It is described in the Chinese chronicle San Guo Zhi and the much later Korean chronicles Samguk Yusa and Samguk Sagi.
In the 1st century AD, the Wolji/Mokji (/) state, that formed and led Mahan confederacy, was defeated in struggles with Baekje, another member of Mahan, and consequently losing whole region of present-day Han River basin. But the San Guo Zhi recorded the Han state fallen in struggles with the Lelang Commandery and Daifang Commandery in the 246. Under continuous pressure from Baekje, only 20 statelets of Mahan confederacy survived until the late 3rd century. Baekje eventually absorbed or conquered all of Mahan by the 5th century, growing into one of the Three Kingdoms of Korea, along with Silla and Goguryeo.
Kings of Mahan occasionally called themselves "King of Jin," referring to the earlier Jin state and asserting nominal sovereignty over all of Samhan. A wealth of bronze artifacts and production facilities indicate that Mahan was probably the earliest developed of the three Hans. At its height, Mahan covered much of the Han River Basin and the modern-day provinces of Gyeonggi, Chungcheong, and Jeolla, although political unity was strongest led by Mokji state (, ) in Cheonan, Chungcheong.
There are three stocks: the first is called Mahan, the second Jinhan, and the third Byeonhan, which is the ancient state of Jin. Mahan is to the west of it. Its people are settled on the land and both sow and plant... Scattered between the mountains and the sea, their settlements have no inner or outer walls... By custom they have few rules and regulations. Their national town has a dominant leader, but the people's settlements are scattered, and they are not readily subject to regulation and control. They do not have the ceremony of kneeling to make obeisance. For their dwellings they make grass-roofed earth-chambers shaped like tumuli; the door is on the top, and a whole family lives together inside, with no distinction as to old or young, male or female... They do not know about riding oxen and horses, their oxen and horses being used exclusively for accompanying the dead... They are strong and brave by nature. They wear the "tadpole knot" and leave it bare like a shining fishtail. They wear gowns of rough cloth, and on their feet they wear leather sandals. When there is something to be done within their community up to the point where the authorities have walls built, all the young braves and stalwarts gouge out the skin of their backs to string themselves together with a large rope, or, again, they insert through their shin wooden poles about a zhang in length. They then chant all day as they work, not because they consider the work painful, but to give themselves encouragement; moreover they consider this to be stalwart behavior... They have a fondness for brigandage... Among their men one occasionally sees one who is tattooed. Moreover on the large islands in the sea west of Mahan there are outlanders, very short and small people whose language is not the same as that of the Han. They all bind their hair like Xianbei, but they make their clothing of leather and like to raise oxen and pigs. Their clothing has an upper part, but no lower part, and indeed it is almost as if they were naked. They go back and forth by boat, buying and selling in the Han.-- Sanguo Zhi
Goryeo historians identified Mahan with Goguryeo, which was supported by their works like Samguk Sagi, Samguk Yusa and Jewang Ungi. That historical view was previously given by Choe Chiwon, a noted Confucian scholar and Historian in the late of the Silla. Apart from the geographical location of Mahan, the Chinese historical record History of Song defines the ethnical origin of the Jeong-an kingdom, a successor state of Balhae, as Mahan.
In the late Joseon period, that historical notion came under criticism by early Silhak scholar Han Baek-gyeom, who emphasized the linkage between Mahan and Baekje in terms of the geographical location.
According to the San Guo Zhi, Mahan consisted of 54 statelets of up to ten thousand families each: