In 1232, Joei Code (militarized Code of Law) was introduced in Nippon. History started to diverge from OTL when in 1274/81 no attack of the Mongols happened on Japan, so no "divine wind" was necessary too. The consequences of this are difficult to estimate - Buddhism, especially Zen Buddhism, stayed a bit weaker. In 1363/64, Black Death was brought to Nippon by ships. Since 1400, the Nipponese started copying Chinese arms (bamboo guns, cannons) - the first ones were smuggled in - and improving them.