faced many difficulties dealing with both new threats, sending many skilled military commanders to the northern front, while contending with Japanese leaders Oda Nobunaga, Toyotomi Hideyoshi and Tokugawa Ieyasu in the south. However, after Toyotomi Hideyoshi unified Japan, the Japanese soon proved themselves to be the greater threat; and many Koreans began to fear that their country would be taken over by the Japanese. Many officials concerned with the defense of the kingdom urged the king to send delegates to Hideyoshi, their major purpose being to find out whether Hideyoshi was preparing for invasion or not. However, the two government factions could not even agree on this issue of national importance; so a compromise was made and one delegate from each faction was sent to Hideyoshi. When they returned to Korea, their reports only caused more controversy and confusion. Hwang Yun-gil, of the Westerners faction, reported that Hideyoshi was raising huge numbers of troops, but Kim Seong-Il, of the Easterners faction, told the king that he thought these large forces were not for the war against Korea, since he was trying to complete his reforms quickly to prevent lawlessness and quash the bandits now roaming the countryside. Since the Easterners had the bigger voice in government at the time, Hwang's reports were ignored and Seonjo decided not to prepare for war, even though the attitude of Hideyoshi in his letter to Seonjo clearly showed his interest in the conquest of Asia. Six-Year War (1592–1598) In 1591, after the delegates had returned from Japan, Toyotomi Hideyoshi sent his own delegates to visit King Seonjo, and asked permission to pass through the Korean Peninsula to invade China, in effect declaring war against the Joseon kingdom. The king was surprised; after refusing the Japanese request he sent a letter to Beijing to alert the Chinese that the Japanese were actually preparing for full-scale war against the Korean-Chinese alliance. He also ordered the construction of many forts in the coastal regions and sent generals Sin Rip and Yi Il to the southern coast to prepare for war. While the Koreans were busy making their preparations, the Japanese manufactured muskets for many of their soldiers, mobilized warriors from across the entire country. On April 13, 1592, about 700 Japanese ships under Konishi Yukinaga invaded Korea. Konishi easily burned Fort Busan and Fort Donglae, killed commanders Jeong Bal and Song Sang-hyeon and marched northward. On the