This is a bit lengthy, but try to bear with me here.
In 1592, Toyotomi Hideyoshi led a Japanese invasion of Korea which at the time was under the Joseon Dynasty at the time with later plans to begin a conquest of Ming Dynasty China. Although the Japanese did come to occupy the entirety of the Korean Penninsula, the combined armies of Ming and Joseon forces which were numerically superior proved too much for the Japanese forces and, in 1598 with a tactical stalemate, the Japanese withdrew for good.
But...what if the Japanese had won?
Lets assume for a moment that Hideyoshi's forces prevailed in the face of superior numbers. What would the implications be of a Japanese victory at the time and beyond?
I addressed this several times in previous threads, in which I concluded that anything more than a temporary occupation was essentially impossible.
Here's some of my responses from
here that quoted previous threads:
This is virtually impossible. While Japan might have been able to hold the peninsula for a few years if things had turned out differently, the invaders would almost certainly be pushed out after the brief occupation. This was mostly because most of the Korean navy and army, which was scattered throughout the peninsula, operated independently of the weak government, and conducted numerous guerrilla operations in order to stall the Japanese . . . your scenario is technically possible only if the vast majority of the generals and admirals are assassinated or butterflied away, which is ASB in itself, and probably not even then, as others will take their place.
It might have had a large army, but the fact that the Koreans matched them in terms of manpower within 1-2 years, despite the fact that it had half the population and was completely unprepared for an attack from the south, suggests that the Japanese would not be able to make significant progress, regardless of the situation. The Koreans had consistently maintained a standing military for centuries . . . In addition, the Koreans were vastly outnumbered in specific key battles, but won many of them, mostly due to the geography and stiff resistance.
Most likely not, as the military assistance by the Ming during the Imjin War was mostly conducted by a token force, and the navy was largely uninvolved.
Extremely unlikely . . . the Japanese would either have to sweep through most of the peninsula, but bypass several key regions, allowing guerrilla forces to eventually wreck havoc, or take Gyeongsang and Jeolla, but allow the Korean army and navy to recover and eventually drive the Japanese out.
To sum up the situation, the quote in my sig [note: deleted a while ago] roughly translates to "[Your majesty], I still have 12 ships," which was stated by Yi Sun-shin in response to the government's order to . . . join the army in 1597. Won Gyun, after being pressured by the government to enact flawed strategies if he didn't want to be imprisoned for treason, had recently lost virtually his entire navy . . . which left Yi Sun-shin to confront around 333 Japanese ships on October 26th with a barely functioning navy. In other words, the Koreans are going to fight to the end regardless of the situation, which means that even if the Japanese managed to gain de facto control over a significant part of the peninsula, the numerous guerrilla campaigns and holdouts will eventually force the invaders to retreat within a few years.
The Koreans lost most of the initial battles against the Japanese because the latter were better trained, although they were stalled multiple times because [of] guerrillas, led by generals such as Gwak Jae-u and Kwon Yul . . . In addition, the naval battles were extremely one-sided, with only one Japanese victory. Most of the guerrilla campaigns were not recorded, but some, such as conflicts in Ichi and Jeongamjin, prevented the Japanese from invading Jeolla in the first invasion. The two generals also came up with ideas to fool the Japanese into retreating without confronting them directly . . . in Jinju . . . [and] Dokwang . . . [causing] the invaders to retreat.
Meanwhile, most of the [Korean] conventional victories on land . . . occurred in the north, when the Chinese began to gradually send reinforcements . . . Even though many of the initial battles were essentially sieges, the Koreans were unable to defend themselves efficiently mostly due to the lack of training, along with low numbers. However, Haengju, which was under Kwon Yul's command, was a notable example in which the defenders won, even though they were outnumbered around 10:1.
In other words, while the Japanese eventually suffered from numerous conventional defeats, causing them to retreat altogether, they were also stalled and defeated by hit-and-run attacks on both land and sea various times beforehand, which severely disrupted their supply and attack routes throughout the two invasions.
As stated above, the Korean navies technically did not directly confront the Japanese ones in order to completely destroy their fighting capabilities, but in order to prevent them from reaching their objectives . . . The first and second invasions also differ significantly in substance, as the Japanese were forced to bypass Jeolla in the first one in order to head north, allowing the Korean navies and guerrillas to attack and resupply from that region, while the second invasion was limited to Gyeongsang and Jeolla, allowing supplies and reinforcements to be effectively stationed in the north, not to mention the Japanese objectives.
[A] combination of conventional and guerrilla warfare contributed to the invaders' eventual defeat. Although the former eventually provided the final blow, the latter was crucial in order to stall the Japanese significantly and eventually prevent them from taking . . . the peninsula, along with allowing reinforcements to arrive from the north.
And here's some of my direct responses:
If the Japanese somehow managed to hold Seonjo hostage, the Japanese might attempt to use this as propaganda, but it wouldn't have made a major difference in the long run. The crown prince was proclaimed due to the war, as there was a deadlock among several candidates, while a potential one had died while fleeing from the Japanese, forcing the ruler to appoint Prince Gwanghae over an unstable prince. Afterwards, while Seonjo continued to head north to the border with the Ming while virtually leaving everyone else behind, the crown prince decided to remain in Pyongyang and resist the invaders by recruiting soldiers while gathering resources in order to aid the people. While I can't find specific figures on the army under Gwanghae's command, I would assume that the majority operated as guerrillas in the mountains, given that they were located in Hamgyeong and Jeolla, suggesting that he actively moved to different regions in need and making it virtually impossible for the Japanese to pinpoint him to a specific location. He also evaded capture when the invaders briefly seized Pyongyang from July of 1592 to January of 1593, again suggesting that he moved around with guerrillas within disparate locations.
These points demonstrate that Prince Gwanghae effectively acted as the de facto ruler after 1592 by commanding troops during the war and supervising the reconstruction process afterwards in place of his father, not to mention that Seonjo personally opposed his son's actions due to the concern that the prince might end up gaining undue influence. As a result, Seonjo's capture might actually cause the people to flock to his son instead, given that he had actively responded to his people's concerns as best as he could.
In terms of military conquest akin to the Imjin War, I discussed
here why it would be essentially impossible for Japan to conquer and hold the peninsula, as numerous generals and admirals operated across the peninsula independently of the government, stalling the Japanese before the Chinese eventually interfered. An earlier war wouldn't have made a significant difference considering the fact that Joseon had continuously stationed at least 50,000 soldiers along the northern border against the Jurchen, most of which would be immediately recalled south if the Japanese appeared. A later war could have been much more disastrous for Japan, as Gwanghaegun, Seonjo's successor, was a skilled diplomat, and might have been successful in reforming the government and the military after avoiding the chaotic aftermath of the Imjin War, strengthening Korea in the long term.
In other words, not only would it be difficult to conquer the entire peninsula, but it would be virtually impossible to retain it for more than 5-10 years or so. If the Japanese somehow attempted to hold onto the peninsula despite numerous setbacks, its treasury would be drained multiple times while suffering numerous casualties, forcing it to spend decades, if not a century, just to recover from the war. Korea would be devastated to a greater extent, but considering that Goryeo recovered after the Mongols continuously invaded for 29 years and despite the fact that its population plummeted at a rate of up to 50%, Joseon would eventually recover, although the costs would certainly be high.
All you have to do is find a way to avoid having Ming jump into the fight. This might actually strengthen the Ming dynasty since the defense of Korea is one of the factors that led to their collapse.
As to later implications: a less isolationist Japan, which may industrialize earlier, a Japan strategically situated to either replace the aging Ming dynasty or conquer Manchuria before going into China.
This is also virtually impossible. Given that Hideyoshi's initial plans included overrunning Korea, China, India, and Southeast Asia, which would have utterly destroyed Japan in every way possible, even if Japan somehow takes over Korea, it will eventually seek to conquer China (Hideyoshi originally demanded that Joseon provide access for an invasion of the Ming, which the former curtly refused), which would result in the Chinese responding with over 500,000 troops (the Ming threatened Japan with 400,000 IOTL, although it mobilized far less than 100,000 in both invasions to defend the peninsula), and a possible invasion of Japan itself, which would utterly devastate both Korea and Japan.
If Japan somehow managed to take over Korea, then directly fight China, the country would probably be even more isolationist than IOTL, as Japan eventually might have experienced a devastating counter-invasion, not to mention that China and Korea would be hard-pressed to normalize relations, forcing the Japanese to rebuild by themselves.
Better still if Yi-Sun Shin dies from the musket ball that only wounded him IOTL at Okpo. His replacement was a disaster, and wouldn't come close to being the thorn in Japan's side that Yi was.
See above. Won Gyun was forced to implement flawed strategies by the government if he didn't want to be accused of committing treason, not to mention that there were numerous talented generals and admirals operating across the peninsula, who collectively stalled the Japanese for several months before the Chinese eventually intervened.
I think the Partisans and Korean Navy would do them in as in OTL. The Japanese Navy had ships that couldn't really use cannons and they were up against the Ming that had better ships and were more experienced against Japanese ships. As a result of not having a good navy they couldn't supply their forces in Korea.
Agreed. See above.
Underestimating the enemy and the victory disease resulting from the earlier success of the campaign eventually created an untenable situation. Hideyoshi's troops literally bit off more than they could chew.Korean naval prowess, although very destructive to Japanese logistics were more of a cap than the single reason the Japanese ultimately failed. The Japanese won essentially every land battle and still there was always more resistance. For Hideyoshi to have a chance of "winning", something that seriously curtails Ming assistance and intervention would need to happen. As it was, I think there were some major rebellions in China during this campaign (if I remember correctly). Japan could have beaten Korean resistance sans the Ming.
What would a Hideyoshi victory have looked like? I suspect it would be more of a temporary truce between a temporarily exhausted or distracted Ming China and Japan. But not a conquered Ming. Although nice softening up of China, Japan, for the Manchu conquest that began not a generation after.
See above. Hideyoshi had already set an impossible goal, and considering the defeats that Japan suffered IOTL, he would either have been bankrupted several times over and/or ousted due to a joint Chinese-Korean invasion of the archipelago, as the court would have been unwilling to rally behind an unreasonable ruler when defeat was in the cards.
The occupation will be temporary, and very draining on Japanese resources until they eventually withdraw or breakdown. Japan will fall into power struggle and Korea will probably fall into power vacuum, which will might be filled by the Manchus.
Agreed as well, although the Manchus would probably leave Korea alone as a tributary for several reasons.
He then executes his full plan, invading China, which given how difficult just occupying Korea was, goes about as well as you'd expect.
Also in agreement.
To be fair, he did have an initial victory in 1593 and signed peace with Ming while still controlling southern Korea, but the problem was the demands of the two sides didn't match, so the two diplomats, Shen Weijing and Konishi Yukinaga, after finding out they were the only people who were bilingual, took liberty in modifying the peace treaty presented to each other.
But in 1596 or 97, Hideyoshi discovered that he was fooled and declared war again in rage, and while Konishi went away in one piece, Shen was executed by Ming Emperor.
Maybe let Hideyoshi stayed fooled for another year or two so he die without discovering it?
See above. The "victory" did not mean much in the first invasion when the Japanese only controlled Gyeongsang, Gyeonggi (including Hanseong), Hwanghae, and parts of Pyonggan (including Pyongyang) and Hamgyeong, while Jeolla, Chuncheong, and Gangwon remained relatively untouched, allowing guerrillas to operate either from the mountains or the navy to resupply from Jeolla, while pockets of resistance continued throughout the peninsula. In addition, both China and Japan demanded that the other recognize each other's ruler as the "supreme" emperor, which would have been unacceptable to their respective parties, forcing another war to settle the untenable situation.
Didn't Hideyoshi start the war the get rid of uppity noblemen, or am I confusing him with another Japanese leader who attacked Korea?
Hideyoshi was the only Japanese leader to invade Korea, with a minor exception in 663 when Tenji invaded Silla with former Baekje troops, although the main reason in terms of social issues was to utilize the large number of
ronin that had nowhere to go after the Sengoku Period theoretically came to an end in 1590 with a nominal unification of Japan.
Hopefully this covers everything.
