Mongol invaders (left) fire on Takezaki Suenaga (on horseback) while a tetsuhau or ceramic projectile bomb explodes overhead
From the 13th century Mōko Shūrai Ekotoba (蒙古襲来絵詞) Japanese handscroll of the Mongol Invasion of Japan

Museum of the Imperial Collections, Tokyo Imperial Palace
Source Wikimedia Commons

Tasuku Ueda, Staff Writer, for the Asahi Shimbun, reports on the possible discovery of Kublai Khan’s invading fleet to Japan –

Matsuura, Nagasaki Prefecture: A wreck found off Takashima Island here is likely part of a Mongol invasion fleet that came to grief in a typhoon more than 700 years ago. The discovery was announced Oct. 2 by archaeologists with the University of the Ryukyus and the Matsuura City board of education who are researching the Takashima Kozaki underwater historic site.

Numerous artefacts have been recovered from the seabed from wrecks of fleets dispatched in 1274 and 1281 to invade Japan. In both invasion attempts, battles were fought in northern Kyushu. The fleet of 4,400 vessels sent by Kublai Khan in 1281 was wrecked near Takashima Island in a storm the Japanese dubbed ‘Kamikaze’ (divine wind) for ultimately saving their homeland from the Mongols.

An earlier report in Archaeology by James P. Delgado describes the discovery by Kenzo Hayashida of the Kyushu Okinawa Society for Underwater Archaeology (KOSUWA) of a, “…tetsuhau or ceramic projectile bomb. KOSUWA has recovered six of these from the wreck. They are the world’s earliest known exploding projectiles and the earliest direct archaeological evidence of seagoing ordnance.” Delado writes –

Chinese alchemists invented gunpowder around A.D. 300, and by 1100 huge paper bombs much like giant firecrackers were being used in battle. Chinese sources refer to catapult-launched exploding projectiles in 1221, but some historians have argued that the references date to later rewritings of the sources. In his recent book In Little Need of Divine Intervention, which analyses two Japanese scrolls that depict the Mongol invasion, Bowdoin College historian Thomas Conlan suggests that a scene showing a samurai falling from his horse as a bomb explodes over him was a later addition. Conlan’s research masterfully refutes many of the traditional myths and commonly held perceptions of the invasion, downplaying the number of ships and troops involved and arguing that it was not the storms but the Japanese defenders ashore, as well as confusion and a lack of coordination, that thwarted the khan’s two invasions. But his suggestion that the exploding bomb is an anachronism has now been demolished by solid archaeological evidence. Moreover, when the Japanese x-rayed two intact bombs, they found that one was filled just with gunpowder while the other was packed with gunpowder and more than a dozen square pieces of iron shrapnel intended to cut down the enemy.

More here and in Archaeology here.