Sansang of Goguryeo

Upon ascending the throne, Sansang married his deceased brother Gogukcheon's widow, Queen U. This marriage was controversial but helped consolidate his claim to the throne and maintain continuity with the previous reign.

The Han dynasty of China launched a major invasion of Goguryeo, capturing several border fortresses. Sansang led the defense, ultimately repelling the invasion but suffering significant territorial losses in the Liao River region.

After the Han invasion, Sansang ordered the fortification of Gungnae Fortress and other key defensive positions. He also reorganized the military command structure to better respond to future Chinese threats.