Gongsun Du (Traditional Chinese: 公孫度, pinyin: Gōngsūn Dù; ?-204) was a general of the Late Eastern Han Dynasty. He did not get the opportunity to really get into battle until Dong Zhuo seized power from Emperor Shao (the former Prince of Hongnong). Dong Zhuo in hoping to expand the empire gave Gongsun Du the command to attack Korea from across the sea. Du was successful in his attack and set up the Daifang commandery and Lelang commandery among others.
Under another order of Dong Zhuo, Gongsun Du took over the Liaoning prefecture. This would be the beginning of the Gongsun power in the North East. Gongsun Du would go on to send Gongsun Muo and Zhang Pi to south Korea in an attempt to gain more land. The campaign was successful and the people of southern Korea were subsequently defeated and made vassals of the Han Dynasty/Gongsuns. In the ninth year of Jian An (204 AD) Gongsun Du died and his son Gongsun Kang took his position and controlled the far northeast.
He was born to Gongsun Du, Governor of Liaodong. In 204 Kang took over the position with the territories of Liaodong, Xuantu and Lelang. He was nominally subject to Cao Cao while keeping his domain semiindependent. In 207 he pleased Cao Cao in killing Yuan Shang (袁尚), the last attested member of the clans of Yuan Shao and escaped the conquest of Cao Cao to Liaodong.
He smashed Yiyimo (伊夷模), King of Goguryeo, at her capital and forced him to move the capital. He separated the southern half from the Lelang commandery and established the Daifang commandery in 204 to make administration more efficient. With military expeditions he brought southern natives into submission.
When he died in 221, his younger brother Gongsun Gong (公孫恭) succeeded him because Kang's children were young. However, Kang's son Gongsun Yuan took back the position in 228.
He was born to Gongsun Kang, Governor of Liaodong, Xuantu, Lelang and Daifang commanderies. After Kang's death, his brother Gong took over the position in 221, but revealed his inability to rule. In 228, Yuan wrested the position.
At that time, China was split into Three Kingdoms. The Kingdom of Wei in the north and Kingdom of Wu in the south made efforts in bringing over the powerful warlord, but his indecisiveness eventually annihilated himself. Although Gongsun Yuan was nominally subject to Wei, Sun Quan, King of Wu, aggressively worked on him. Yuan considered switching sides to Wu until he yield under the pressure of Emperor Ming of Wei. Yuan killed Wu delegates, but some of them fled to Goguryeo, who was suffred from constant pressure from the Gongsun family. Then Wu allied with Goguryeo to launch a pincer attack against Yuan. However, Goguryeo was nervous about the risk and killed Wu delegates.
Feeling a sense of crisis, Emperor Ming decided to overthrow the Gongsun family. In 237, he dispatched Wuqiu Jian with Chinese, Wuhuan and Xianbei troops, but the campaign was aborted due to floods. Gongsun Yuan proclaimed himself as the King of Yan (燕) and concluded an alliance with Wu. In the next year, Sima Yi and Wuqui Jian attacked Liaodong again. As a result of the campaign, Gongsun Yuan was killed and the Gongsun family was exterminated. The Kingdom of Wei conquered Liaodong and northwestern Korea.