User:Susubi2007/17th Year Battle of Yeongnak

In the 17th year of Yeongnak (407), Gwanggaeto the Great of Goguryeo dispatched an army of 50,000 troops to annihilate the Later Yeon army, obtain loot, and occupy several castles. The name “Battle of the 17th Year of Yongnak” is not an official name

Background
The relationship between Goguryeo and Later Yan was very bad. In February 400, when Gwanggaeto the Great's main Goguryeo army was repelling the Japanese army in Silla, King Murong Sheng of Later Yan attacked Sin-Castle(新城) and Namso-Castle(南蘇城) Fortress, and in 402, Gwanggaeto the Great the Great attacked Sukgun-Castle(宿軍城) of Later Yan. The castle was attacked and captured. And King Gwanggaeto the Great invaded and conquered Later Yan in 404. When Later Yan attacked again, Gwanggaeto the Great defeated them at Liaodong Castle in 405 and Mokjeo Castle(木抵城) in 406, solidifying his occupation of Liaodong. Gwanggaeto the Great once again mobilized 50,000 troops and defeated the Later Yan army. This is the 17th year of the Battle of Yeongnak. Later Yan, which declined militarily and faced difficult times for the country, fell in 409.

Result
They captured a huge amount of loot and captured six castles in Later Yan on their way back. In order to keep the Later Yan in check, friendly relations were established with the Southern Yan.