What contributed to the failed monogol invasions of japan?

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The Mongol invasions of Japan (元寇 Genkō), which took place in 1274 and 1281, were major military efforts undertaken by Kublai Khan to conquer the Japanese archipelago after the submission of Goryeo (Korea) to vassaldom. Ultimately a failure, the invasion attempts are of macro-historical importance because they set a limit on Mongol expansion and rank as nation-defining events in the history of Japan.