忽必烈六次遣使招諭日本通貢，但京都朝廷與幕府均認為蒙古國書措辭無理，有威脅日本之意，而未與回覆。面對將與蒙古對決的危機，當時日本舉國上下一致祈禱，希望藉由神力、佛力擊退敵人。掌握實權的幕府，軍事上的措施，主要是以九國輪番守備，並於博多灣沿岸建造防壘，加強防衛。 元軍二次征日，應戰日軍則僅限於東國及在九州擁有領地的武士，是以守護、地頭領導的個人軍團為中心，多者百餘騎，少者僅數騎而已。元軍在兵士人數和武器裝備上，均較日軍佔優勢。但因軍隊素質不一，將帥不合、怯戰，軍隊會合地點一再變更。又因跨海作戰，糧食、馬匹運輸困難，且二次均遭遇大風，船艦停泊海上，無法避風濤，以致失利。反觀由個別武家軍團組成的日軍，其參與戰鬥，雖為取得功勳，並無國家、民族意識，但上下主從關係，使各單位內將卒的團結極為穩固。而且有海的地利，船小可靈活出擊，尤其得大風之助，因此二次均能渡過危機。 明治時期，開始將二次元軍的敗退，視為「神風」的威力。二十世紀前半，日本積極對外擴張，為提高國民戰意，「神風」更廣泛被利用。

Kublai had ever dispatched messengers for six times to Japan, and expected that Japan could present tribute to the Yuan Dynasty, however, both Bakuhu and Court in Japan believed that wording of the Mongolian Credentials were unreasonable, that was with the purport of threatening Japan. At that time, Japan was in the entire nation to pray for subjugate the hostile country though it was in the face of the crisis of war against Mongol. The defense measures of Shugo and Zitou were mainly that nine nations garrisoned in turn and constructed defensive ramparts along the coast of Hakata bay. The Japanese army that prepared against war was led by Shugo, Zitou, ruler and subjects were of one heart and mind, their solidarity was quite secure, their morale of fighting was strong. However, their making-war-way and weapons were inferior to the mongal's. Military of the Yuan dynasty had been twice to attack Japan, but both the two attacks had ever come across windstorm. At that time, such windstorm was regarded as Kamikaze by the government and the people of Japan, and meanwhile they believed that it was the result of praying in the entire nation to God with great enthusiasm.