In the late thirteenth century, the Mongol Empire under Kublai Khan made two unsuccessful attempts to invade Japan. Historian Kawai Atsushi gives the background to the invasion, examines different theories about reasons for its failure, and looks at the aftermath for both sides.
In November 1274, a fleet carrying some 30,000 Mongol Empire troops approached Hakata Bay off the Japanese island of Kyūshū. Genghis Khan had established the empire in the early thirteenth century by unifying the nomadic peoples of the Mongolian Plateau. Successive leaders expanded the empire through central Asia, and made Goryeo (Korea) a vassal state in 1259. At the time of the invasion, the Mongol holdings stretched from western Asia and Russia to northern China and the Korean peninsula.
Seeking a southern base, in 1264 Kublai Khan had moved the capital from Karakorum to the new city of Khanbaliq (now within the modern city…