Korean War of 1592-1598

The Japanese invasions of Korea (1592-1598) comprised a major war between Japan and the alliance of Ming of China and Joseon of Korea. Japan invaded Korea on May 23, with the larger objective to conquer the entirety of Asia by using Korea as a land bridge to China. The battles that involved 300,000 combatants and claimed more than 2 million lives took place almost entirely on the Korean peninsula and its nearby waters. The war consisted of two main invasions from Japan – the first in 1592 and 1593, and the second from 1597 to 1598.

Toyotomi Hideyoshi, the predominant warlord in Japan, had for long been aspiring to leave his name in history as a great conqueror of Asia. Even before unifying all of Japan in 1590, Hideyoshi began sending ambassadorial missions in 1587 to Korea to reveal his intention to have Korea join with Japan on war against China. Hideyoshi had been under the false impression that Korea was a Japanese territory as a part of the Tsushima Island, when in fact Korea was a vassal state of China. When Korea rejected Hideyoshi's "decree" in 1592, Hideyoshi launched the invasion late in April and commanded his forces in absentia.

The Japanese troops first attacked the southeastern part of Korea and then advanced northwestward to the capital. The Korean capital city of Hanseong fell within 3 weeks and most of the peninsula came into Japanese control by end of the year. China responded by sending 3,000 troops to the city of Pyeongyang in late August, but the Chinese were horribly outnumbered and defeated by the Japanese troops. However, within a few days of the Chinese defeat, the Korean admiral Yi Sun-sin annihilated the Japanese fleet carrying the reserve troops that would continue the invasion into China. On January 1, 1593, the Chinese launched a counter-offensive with 50,000 troops and reclaimed Hanseong by the middle of May. With the southeastern parts of the peninsula in Japanese possession, the two sides spent several years in diplomatic talks; the Japanese officials justified their invasion by asserting that Korea carried out policies to prevent Japan from entering the Chinese tributary system. Consequently the Chinese diplomats went to Japan and invested Hideyoshi, whose subordinates misled him into believing that the Chinese had come to surrender in person. The peace negotiations culminated in another invasion of Korea by the Japanese troops in October of 1597 when Hideyoshi found out the truth behind the Chinese visit and was greatly offended. Hideyoshi's forces saw very little success and, as ordered by Hideyoshi, began to withdraw late in 1598. The war ended middle in December with the naval battle at the straits of Noryang, where the Korean and the Chinese fleets sunk over 300 Japanese ships carrying as many as 10,000 lives.

The war is known by several English titles, including the Hideyoshi's invasions of Korea, in context of Hideyoshi’s biography; the Seven Year War, in reference to the war’s duration (the fighting continued even during the peace negotiations); and the Imjin War, in reference to the war's first year in the sexagenery cycle (in Korean).

Background

East Asia and the Chinese Tributary System

The war took place within the context of the Chinese tributary system that dominated the East Asian geopolitics. In practice, the tributary states periodically sent ambassadors to the Chinese imperial court to pay homage and to exchange gifts, while maintaining complete autonomy. Many of the tributary states received from China the rights toward the international trade within the tributary system. The theoretical justification for the tributary system was the doctrine of the Mandate of Heaven, that the Heaven granted the Chinese Emperor the exclusive right to rule, with the purpose of benefiting the entirety of mankind. Several Asian countries, including Korea, voluntarily joined the tributary system in pursuit of the legal tally trade and the legitimacy in their rule through the doctrine of the Mandate of Heaven.

Japan actively sought to engage in the tributary trade and attained from China the two treaties, in 1404 and in 1434, that admitted Japan into the tributary system and required Japan to police its waters against the wako pirates. However, as the Japanese lords failed to effectively control its piracy, China expelled Japan from the tributary system in 1547. The trade issue would emerge again, during the wartime negotiations between Japan and China, as a cautious excuse from the Japanese to justify their first invasion of Korea.

China came to Korea's aid during the war mainly because of Korea's symbolic importance to the Chinese. The Chinese and Koreans considered themselves as the pinnacles of civilization, similarly to today's cross-national cultural identities (such as "the West") based on scientific and academic achievements. The very strict Confucian ideologies that imbued the two countries contributed to this elitism by rejecting the foreign customs and learnings as immoral and barbaric. Additionally, China had to fulfill its promise to provide security to its tributary states. The Chinese authorities feared greatly that the China's loss of legitimacy on this occasion would spur a domino effect of opposition, collapsing the entire tributary system. If not, still the loss of Korea to Japan meant that China could no longer outflank the northern region of Manchuria, in its war against the hostile Jurchen tribes.

Military situation

This conflict played out to be one of the earliest cases of modern warfare in Asia. The Sino-Korean alliance and the Japanese deployed troops across the peninsula number in several hundreds of thousands, in a constant exchange of technological innovations and tactical strategic adaptations. Of all factors that influenced the direction of the war, military technology most heavily contributed to the Japanese retreat from the peninsula by 1598.

An illustrative example of the war's modern attributes is the participants' extensive use of European firearms. While primitive firearms had seen a limited but continual production in China (for 200 years) and a temporary existence in Korea, the advanced muskets that would be used in the war were first introduced in 1543 to Japan by the Portuguese traders on the island of Tanegashima.

The Portuguese arquebus received mixed reaction from the Japanese, who had experienced by then nearly a century of civil war. The Japanese observed several inconveniences with the new long-ranged weapon, including the slow loading time between each shot and its poor accuracy. A warlord named Oda Nobunaga overcame the deficiencies by arranging his men to fire their guns in concentrated volleys, and conquered with success a third of Japan before his assassination in 1582. Toyotomi Hideyoshi, one of Nobunaga's followers who came out to be successful in the ensuing power struggle, continued Nobunaga's conquest up to the unification of Japan in 1590.

By the end of civil war in Japan, Hideyoshi had built up an army of 500,000 veteran troops. The army consisted mostly of infantry and partly of cavalry, and the infantry further divided into archers, spearmen, and gunners. The flawed, conventional view of the war in brief is that the Japanese, equipped with superior weapons (mainly the muskets), were winning the war against the Koreans until Admiral Yi developed the iron-clad turtle ships, and the Chinese joined the Koreans to simply outnumber the Japanese. There are several reasons why this perspective became dominant. First the Japanese chroniclers who worked for the Japanese commanders often exaggerated the accomplishments of their employers and inflated the number of enemies. Second, in Korea and China, the established historiographical practices limited the historians to a framework of praise and blame in their analysis, and made inevitable their emphasis on the military weakness of Sino-Korean alliance. Finally, these early misinterpretations provided a firm basis for the later scholars to continue the myth of Japanese victory.

In fact, the Korean troops were, on the most part, very poorly organized, equipped, and trained. The 200 years of peace in Korea necessitated the Joseon government to fund its military at a minimum level, and, in contrast to the Japanese, the higher-ups of the Korean military tended to be officers with political connections rather than individuals of merit. The only

a close-examination of the primary sources reveals that the Japanese disliked risking in full-scale fighting with the Chinese because of their superior military machines. The Chinese deployed no more than 80,000 soldiers during any stage of the war, and, on most occasions, the combined allies maintained only a slight advantage over the Japanese in number. The Japanese lost their monopoly on the match-lock guns when the Koreans began manufacturing them early in the war, but the allies maintained their superiority in artillery technologies all throughout the war. The use of the muskets was much more common among the Japanese troops, but, even then, the Japanese muskets with a maximum range of 600 yards did not completely outdate the Koreans' composite-reflex bows with a similar limit of 500 yards (the Japanese bows had a range of 300 yards).