Hong Ta-gu (Korean: 홍다구; Hanja: 洪茶丘; 1244–1291) was a Goryeo commander of the Yuan dynasty.
There were a few tens of thousands of Goryeo warriors in Liaoyang and Shenyang, and Kublai demanded their loyalty under threat of punishment for their families.
In 1269, when Im Yon attempted to remove Wonjong from power, Hong received orders to invade Goryeo with 3,300 men.
In 1273, Hong carried out the mass slaughter of rebel prisoners when Yuan and Goryeo troops took Tamna, the last stronghold of the Sambyeolcho.
In April 1274, the Yuan instructed Holdon and Hong Ta-gu to mobilize 15,000 men for the invasion of Japan.
Hong was put in charge of the construction of large transports and was harsh and cruel in exploiting the Goryeo people for the project.
[2] During the actual invasion, one of the three commanding Yuan generals, Liu Fuxiang (Yu-Puk Hyong), was shot in the face by retreating samurai and seriously injured.
Holdon wanted to keep advancing through the night before more Japanese reinforcements arrived, but Hong was worried that their troops were too exhausted and needed rest.
He attacked a popular Goryeo general, Kim Pang-gyŏng, who had fought the Mongols and afterwards sought establishment of friendly ties with the Yuan court.
Kim also led Goryeo forces in the Sambyeolcho Rebellion and invasion of Japan, which naturally threatened Hong's position.
The History of Yuan says that Chung-hŭi served in the emperor's guard in 1276 and in 1279, he inherited his father's position as Commander of Goryeo Warriors.
When Chungseon of Goryeo came to power in 1309, both brothers criticized his administrative reforms and proposed sending warriors from Shenyang to cut lumber in the Paektu Mountain region to provoke conflict.
Chung-hŭi argued that it was unreasonable for one person to sit on two thrones at the same time, referring to Chungseon's position as both king of Goryeo and Wang of Shenyang.
Chungseon also benefited from three rest stop villages established by Kublai in 1279 between Goryeo and Khanbaliq that became his base for expansion into Liaoyang.