Nicephoric War

The Nicephoric War, also recognized as the War of Seleucus Nicephorus, the Xuchang War, the War of the Xuchang Alliance, and the Grand Campaigns Towards the Far Edge of the World, was a military conflict that was instigated by Seleucus XII Nicephorus against the Far East nations of Imperial Goguryeo, the Han dynasty, and the Xianbei Confederacy, collectively known as the Alliance of Xuchang. It lasted from 201 to 209, resulting in a Seleucid victory.

Informed of the formation of the aforementioned Alliance three months before the war's start, Seleucus and his government recognized the threat the Alliance posed to the Empire's power. The monarch, seeking vengeance against Bosucheon of Goguryeo and the expansion of Seleucid power with his firm belief in the Eastern Mission, decreed to declare war against the Alliance.