alternatehistory.com

My POD starts from the traditions of the Heike monogatari because I do not know what actually occurred and involves the relationship between Minamoto no Yoritomo and his younger half-brother Minamoto no Yoshitsune. It is ASB because it posits that Yoritomo actually likes his half-brother. Thus after the great victory of Dan-no-ura in 1185, he considers how to maintain a good relationship with Yoshitsune while making himself Shogun. He concludes that he needs to keep Yoshitsune occupied and thus send him, leading an army including other warriors such as former Taira who Yoritomo does not completely trust, to conquer Taiwan (I also considered Korea or the northern islands of Hokkaidō and Sakhalin/Karafuto but a northern expansion seemed less likely to cause significant effects while Korea could probably not be taken). Given reasonable luck, I suspect that Yoshitsune could have persuaded most of the tribes of Taiwan to give tribute (assuming that he did not demand too much) and accept Japanese rule.
Thus by Yoritomo's death in 1199 (or perhaps later if Yoritomo's horse is not startled by Yoshitsune's ghost), Yoshitsune is governor general of Taiwan. By 1280, when Japanese rule might face a Mongol challenge, I assume that Japanese is the single most spoken language on Taiwan. Thus even if the link is sometimes broken, I can imagine that it will tend to be restored whenever a new Shogunate is established, such as the Hojo to Ashikaga transition, as defeated remnants will otherwise retreat to the Fifth Island. Thus it becomes much harder for a new Shogun to avoid contact with the outside world while unifying Japan.
Top