Japanese Blitzkrieg : 「文禄の役」の侵略図
With Choson enmeshed in factional squabbling, Hideyoshi readied his forces to move into Choson. From his headquarters in Hizen, Hideyoshi mobilized seven fully-equipped divisions, nearly 150,000 men and gathered a fleet of some 700 ships, transport vessels, naval ships and small craft to move his army across the Tsushima Strait. Many of the approximately 9,000 seamen who manned the Hideyoshi's fleet were reportedly former pirates. From their advanced staging area on Tsushima Island, an expeditionary force of three divisions (51,000 men) sailed for the south Choson coast near the end of May 1592 : 11,000 men under General Kuroda Nagamasa, 18,000 men under the leadership of General Konishi Yukinaga, a Christian born of a merchant family from Sakai, and 22,000 men commanded by General Kato Kiyomasa, a Buddhist "mustang" officer who rose from the ranks with Hideyoshi.
Pusan garrison troops under the command of Chong Pal manned beachhead defensive positions around Pusan To the north, a few miles inland at the small town of Tongnae, town magistrate Song Sang-hyon commanded a small civil defense force. General Konishi reached the port of Pusan a full five days ahead of generals Kato and Kuroda.The Japanese surprised and quickly overwhelmed the badly outnumbered defenders in both Pusan and Tongnae. Despite bravely defending the beachhead areas to the death, Choson's garrison troops proved no match for Japanese soldiers armed with short-range brass cannon and matchlock muskets. Moreover, they faced an army with extensive combat experience, men already bloodied from the many campaigns of Japan's Warring States period.
General Konishi had already established a beachhead in Choson by the time Kato and Kuroda's two remaining divisions reached Pusan. The combined Japanese army was too large to advance along a single route, particularly since the troops would have to live off the land. The Japanese left Pusan in three separate columns, opening a three-pronged northward assault toward the capital in Seoul. By messenger and beacon fires, reports of the invasion quickly reached the Yi court in Seoul along with reports of the many towns captured by the Japanese. Stunned by the news, King Sonjo's government panicked. The Border Defense Command quickly issued orders to call up the scattered remnants of the Choson army.
The government placed its hopes on the talents of General Sin Ip, a tough military fighter who had won earlier fame in successful campaigns against the Jurchen in the northern provinces. General Sin received orders to take all the men he could muster and contain the Japanese in the Naktong River basin by blocking the three mountain passes leading out of Kyongsang Province. Sin mustered a few thousand untrained men armed only with spears, bows and arrows. The leadership of this ragged group was even worse than the condition of the troops. Well before his small force reached the first of the mountain passes, General Sin received disturbing, detailed reports describing the Japanese army's battle prowess. Instead of taking the high ground, where tens of men could defend against thousands, the doughty general decided to wait for the advancing Japanese behind a strong defensive position established on an open plain near the city of Ch'ungju, where he felt his men would fight better than in the mountains.
General Kuroda's division swept westward through the Sobaek Range over the Ch'up'ungyong Pass and proceeded north through the western provinces toward Seoul. General Konishi's division moved virtually unopposed up the center of Kyongsang Province. Meanwhile, General Kato's division, the third prong of the Japanese assault, drove north from Pusan toward Kyongju, turned northwestward, then linked up with Konishi in the valley near Ch'ungju. After crossing the undefended Oryong Pass, Konishi's soldiers moved into the lower Han River valley, where the Japanese met their first strong resistance from General Sin Ip's rag-tag army. In the bitter and bloody fight that ensued, Japanese troops overran the Ch'ungju defenders and killed General Sin. The two Japanese divisions continued their march toward Seoul along two different routes. The main objective of the assault on Korea was plunder. The Japanese deployed six special units with orders to steal books, maps, paintings, craftsmen (especially potters) and their handicrafts, people to be enslaved, precious metals, national treasures, and domestic animals. Meeting little resistance, the Japanese ravaged the civilian population. Entire villages were swept up in the raids. Japanese merchants sold some to Portuguese merchants anchored offshore and took the rest to Japan.
The relentless Japanese advance toward Seoul caused turmoil among the local population already gripped by confusion, fear and panic. Thoroughly alarmed and near panic themselves, King Sonjo and his court decided to flee north from Seoul to Kaesong. The government made no attempt to defend Seoul, but Sonjo ordered his two sons into the northern provinces of Hamgyong and Kangwon to raise fresh troops for the army. Neither of Sonjo's sons found anyone who would respond to their pleas to help defend the country against the Japanese. In the end, the Japanese captured both Choson princes.
King Sonjo made hasty preparations to abandon the city to the advancing Japanese. He gathered his family and with his retinue of high court officers fled through the west gate of the city along the "Beijing Road." When word of the impending royal evacuation reached the streets of the capital, citizens blocked their exit, hurling insults and stones at them. After fleeing the city to the north, the band of less than courageous aristocrats arrived in Kaesong only to be met again by local citizens armed with anger and masonry. Seven days later, the royal retreat finally crossed the Taedong River and halted in P'yong'yang.
Infuriated by the government's incompetence and irresponsibility, the people of Seoul erupted in a furious rage. They placed the full blame for Choson's wretched state of affairs squarely on the backs of government officials, men who had failed to concern themselves with the welfare of the people and had permitted the farming villages to fall to ruin. Mobs of people swept through the city looting and burning government storehouses. The city's slave population attacked and burned the offices of the Ministry of Punishments and the hated Ministry of Justice. In their fury, mobs of angry citizens destroyed large numbers of census registers and the archives which held the slave-deeds. The destruction of the census registers and numerous other documents that recorded the status of Choson citizens by the Japanese freed many slaves from their bondage.
Less than three weeks after departing Tsushima Island, Konishi Yukinaga's division triumphantly marched through the South Gate into the city of Seoul. By late spring, all three of Hideyoshi's vanguard divisions occupied the Choson capital. Hideyoshi landed the remainder of his army on the nearly defenseless southern coast to occupy Kyongsang Province. There the Japanese quickly began to organize feudal land holdings similar to those in Japan for distribution to victorious commanders.