Admiral YI Sun Shin

After many centuries and continuous Chinese dynasties upholding strong riverine and oceangoing navies (riverine to patrol the rivers and lakes in the southern half of China to maintain forces against rebellion and defense in general, oceangoing to escort and protect merchant fleets traveling abroad) the exploits of Admiral Zheng He in the previous 15th century seemed to mark the height of Chinese naval superiority in the East, as the Ming oceangoing navy was largely disassembled after his voyages. This was because of internal policies against expenditures that seemed frivolous, unneccessary, and favoring to eunuchs by the Confucian gentry-scholar elite, who retook power of Beijing away from the hands of the eunuchs (and of course, Zheng was a eunuch). With the policies of largely shutting their doors to trade, determining that China could produce most of what she needed within her own realm, the situation was only exacerbated with Japanese pirates raiding the eastern coast in the mid 16th century. This was concurrent with European merchants (as well as missionaries) who came into the scene and filled the vacuum of trade between China and Japan after China had pretty much excommunicated Japan from direct trade (Japan still assumed trade of incoming mainland goods by trading with China's trade partners, including Korea). As for the presence of the Ming navy in the Imjin War, they weren't entirely absent, since they fought all the way up to the last battle of the war, the Battle of Noryang Point. After leading the Japanese into an ambush at the narrow straight, the Koreans and Chinese shelled the Japanese ships from afar until the Chinese under Chen Lin, seeing that the Japanese under Konishi had suffered considerable damage, charged with his ships to engage in fierce melee, grapple-and-board style combat. With this the Japanese actually had a chance to inflict some damage with close range firing and grappling onto Chinese boats, and when Chen's flagship came under direct attack, Admiral Yi Sun Sin gave command to sail up ahead as well. This was the decisive last blow to the Japanese, and much like Nelson at Trafalgar, Admiral Yi was killed in the end, killed by a stray Japanese bullet.