Causes of Piracy in Medieval Japan

Causes of Piracy in Medieval Japan

By Joanna Abeli

Senior Honors Thesis, Eastern Michigan University, 2011

Abstract: In this thesis, I examine why there were phases of intense international raiding by Japanese pirates during Japan’s medieval period. The scope of the study spans two distinct phases of piratical activity by Japanese marauders known as the wako, the first lasting from 1223 to 1265 and the second from 1350 to the early 1400s. As the wako have been studied before from the perspective of the central governments of the period affected by the raiding, namely those of Japan, China, and Korea, this is an examination of the causes of piracy from the perspective of those on the periphery of Japanese society.

I argue that the first phase of wako activity commenced largely as a response to the desertion felt by those living in the Kyushu region of Japan. This desperation was caused by severe natural disasters, increased taxation by corrupt officials, and a generally heightened level of violence following the brief period of civil war preceding the raids. I also investigate the effects external factors such as extra-legal trade and foreign relations had in creating an environment conducive to raiding. The role of the Mongol invasions of Japan at the end of the thirteenth century as a break between the two phases of wako activity is also given considerable attention.

I then examine the second phase of Japanese piracy and explain the shift in factors that caused this phase to be so much more devastating than the first. Particular attention is given to profit than desperation as a motivating factor for the pirates, the civil war raging throughout Japan at the time, the militarily weakened state of the Korean peninsula, and the resumption of international relations between Japan and its neighbors. Finally, I will examine the strategies of Ming China and the Choson Court in Korea to suppress these raiders and why the Korean model was ultimately successful in bringing nearly two hundred years of Japanese piracy abroad to a close.

Click here to read this thesis from Eastern Michigan University

Click here to see our review of The Mongol Invasions of Japan 1274 and 1281 

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