First Mongol-Goryeo invasion of Japan Succeeded

In an anime forum, I posted the titular question, which was responded by this answer below :

The Mongol-Goryeo forces were pretty close to taking all of Kyushu in the first invasion, but it failed when the Mongol commanders chickened out and ordered the retreat to the boats, eventually being sunk. The second invasion, on the other hand, had almost no chance of succeeding, with the Japanese being ready.

If the Mongols hadn't boarded their ships during the typhoon of the first invasion, they could have taken Kyushu in that attempt. There seemed to have been a clash between the Koreans (who advocated staying on land) and the Mongols (going back onto the ships), and OTL was decided by the Mongols. With the Japanese forces having their back to the wall (only one fortress remained), an intact invasion force would have been able to conquer Kyushu and perhaps head for Western Honshu.

The one change which would be needed to have the first invasion be successful (not necessarily conquering Japan, but succeeding in invading Japan): Don't get on the ships. Really, the thing was that Kyushu was about to fall, with reinforcement being weeks away. One more push by the Mongol-Goryeo forces would have meant complete occupation of Kyushu.



Should the invasion had succeeded, I can see Korean influence being dominating in Japan. The unique position of Goryeo within the Yuan sphere had allowed the Goryeo king to have the title "King of Shenyang," a basis that would later result in Yi Songgye's rebellion when he was sent to invade Liaodong. Given that the most important fighters of the Mongol forces were the Koreans, and it was the Goryeo King at the time (Chungnyeol) who ultimately pushed for the invasion of Japan, I can certainly see the Goryeo court having great influence over the affairs of the conquered Japanese islands.



The question is, how would the Goryeo court have influence in the conquered parts of Japan. I can see three ways to this:

1. Trade/Cultural exchange: With the subjection of Japan, the threats from the Wakou pirates would have decreased, and as such trade and cultural exchange would most likely have been higher. Korea would most likely have recovered far faster from the damages of the Mongolian invasions, and the higher population would only have to face the dangers mostly from the north. Also, influence would naturally grow.

2. Population movement: The "King of Shenyang" title was originally given because of the large amounts of Koreans who moved to and lived in Liaodong. If Japan is occupied, I can see a sizable number of Koreans going to Kyushu, and setting up communities. This means that Koreans would be setting root in Japan as never before since the fall of Baekje, and that in itself would be another strength for Goryeo.

3. Title: It was the Goryeo King that pushed for the invasion, and as such he would have a say in the administration of Japan. Even a small role would have large repercussions, and there is always the possibility that he would have received an honorable title concerning Japan. This would most likely link Korea to Japan. Add in possible intermarriages between the royal families of Yuan, Goryeo, and Japan, and you have in-laws connecting from Dadu to Kyoto.


This in turn got me more interested about Korean history. Say, how do you think Korean hegemony or at least partial occupation over Japan will perform here, and for how long will it last ? I'm quite excited by the motions of Korean community established in Japan (which will most likely remain distinct from the natives if they're based on Kyushu) and a more open Japan in general (even with only Kyushu, I don't think its later reconquest by Japan will eradicate the trade connections with Asia established there by the Koreans. If anything, they'll just overtake it).

On the other side of the fence, there are some interesting notes. First, Zen Buddhism received a boost from victory over Mongol-Korean invasion, so did Japanese exclusivist tendency. Second, the opinions between Shogunate and the Imperial court differed about Mongol vassalage. The later was willing to submit but due to their political impotence nobody listened and the Shogunate persisted to refuse Mongol demands. The interesting part about it is that around this time The Imperial Court was still vying to wrestle effective political power from the Kamakura Shogunate(indeed, years after the Mongol invasion, Emperor Go Daigo plotted to overthrow the Shogunate). Had Kyushu fallen, I wonder if the Imperial Court's opinion will catch enough ears, which in turn raise the question how will Mongol-Goryeo campaign for Japan conclude afterward. Here are several possibilities that I can think of :

1) Japan decides to surrender after the fall of Kyushu.
2) Japanese civil war between Kamakura and Imperial Court will follow the fall of Kyushu, which will certainly be exploited by the invading force.
3) Japan remains united in resistance to Mongol-Goryeo advance.

I wonder which of the three possible scenarios would be the most likely to happen, and how it will conclude. Thoughts ?
 
I'm not sure how accurate your sources are, but somethings to point out: I don't know how much the Korean leaders pushed for war, but the attack on Japan was already on the Mongol agenda. Also, it's 600 miles between Hakata Bay and the seat of Hojo power in Kamakura. From a quick bit of research, nobody, not even the Mongols, simply walks into Kamakura. The Japanese court rarely, if ever, married outside the Fujiwara, so I don't think a Mongol or Korean occupation of Kyushu is going to persuade the Emperors to start doing so.

The first option is not going to happen as long as the Hojo are around. The second and third are possible, but I think the third is the most likely, since the imperial leaders at this time don't seem ambitious enough to me to rebel just to submit to the Mongols.
 
Keep in mind that the late Koryo royal family and many noble families became pretty Mongolized due to lots of intermarriage and Korean princes often staying in the Mongol capital.
 
The second scenario seems like it could be the most interesting. Would it be possible for one of the sides in the conflict to get Mongol support in exchange for accepting status as a tributary state, and possibly giving up Kyushu? The Kamakura could get the title of "King of Japan" from the Mongols, which would provide some legitimacy. Though some would say that the Japanese would never give up their Imperial line, I've never been convinced that that is so set in stone.

I'm not sure how useful it is to talk about the openness of Japan or the supposed exclusionary tendency if we're discussing this period. A Japanese tied into the Yuan dynasty tribute system may have greater links with Continental Asia, but even if it stays in the tribute system that doesn't mean it will necessarily be better equipped to deal with European interlopers. Centuries of relative peace within the tribute system and a more conservative government influenced by China may be less likely to open up to Western trade and influence than OTL Japan was, and perhaps ultimately more vulnerable to depredation.

But that's not even considering that the Kyushu thing might end up being a big problem with far reach. Korea will have interest in trying to keep Japan weak, while Japan would likely have a deep desire to reclaim their territory. A period of weakness or chaos in China (such as the fall of the Yuan), could see further Korean-Japanese wars.
 
On the other hand...another possibility. Goryeo eventually overthrown in Korea by neo-Confucian *Joseon, flee to Japan? Buddhist Japanese-Korean fusion kingdom in Kyushu? Could be cool.
 
Frankly, I'm not very convinced that Mongol-Korean invasion could've subdued the entire Japan, but on the other hand quite am that Kyushu will be Korean for quite a while, simply due to its proximity to motherland and Korean naval supremacy.

OTOH, I'm also still not convinced that Kyushu will be their limit.

Naval superiority is the primary factor here. With Kyushu as a base, Korean naval reach can be quite far into deeper parts of Japan, Kansai certainly included. Also it seems that Japanese armies that time tended to be pretty small, certainly compared to contemporary Asian armies. If Kamakura could have counted on the solid political ground domestically, it still seems that weathering the sheer resources of the Mongol-Koreans will be a tough a job.

I'm inclined to predict that Kansai will be the frontline. Or even Chubu. A period of a divided Japan seems pretty possible here.
 
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The second scenario seems like it could be the most interesting. Would it be possible for one of the sides in the conflict to get Mongol support in exchange for accepting status as a tributary state, and possibly giving up Kyushu? The Kamakura could get the title of "King of Japan" from the Mongols, which would provide some legitimacy. Though some would say that the Japanese would never give up their Imperial line, I've never been convinced that that is so set in stone.

I'm not sure how useful it is to talk about the openness of Japan or the supposed exclusionary tendency if we're discussing this period. A Japanese tied into the Yuan dynasty tribute system may have greater links with Continental Asia, but even if it stays in the tribute system that doesn't mean it will necessarily be better equipped to deal with European interlopers. Centuries of relative peace within the tribute system and a more conservative government influenced by China may be less likely to open up to Western trade and influence than OTL Japan was, and perhaps ultimately more vulnerable to depredation.

But that's not even considering that the Kyushu thing might end up being a big problem with far reach. Korea will have interest in trying to keep Japan weak, while Japan would likely have a deep desire to reclaim their territory. A period of weakness or chaos in China (such as the fall of the Yuan), could see further Korean-Japanese wars.

I'm pretty convinced that Japanese royal family will side with the Mongols. OTOH, it will may provide an excuse for Kamakura to denounce them.

I tend to think that the Japanese exclusionary tendency IOTL began with victory over Mongol invasion. As for how TTL Japanese will fare with Europeans, I agree that it will depend on factors, but more open-ness and active foreign policy should increase the odds.

It does seem that Kyushu thing will become a serious point of contention, should we go that way.
 
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The second scenario seems like it could be the most interesting. Would it be possible for one of the sides in the conflict to get Mongol support in exchange for accepting status as a tributary state, and possibly giving up Kyushu? The Kamakura could get the title of "King of Japan" from the Mongols, which would provide some legitimacy. Though some would say that the Japanese would never give up their Imperial line, I've never been convinced that that is so set in stone.

Again, the Kamakura Shogunate is unlikely to accept being tributaries of the Mongols, and the imperial family probably wouldn't accept such a subordinate status. After all, about 700 years before the Mongols came, the Japanese Emperors already thought of themselves as equals with the Chinese ones.

Even if the Kamakura Shogunate gave up Kyushu, I don't see it being displaced by direct imperial rule. As for the imperial line, the only way I could see Japan lose it is if the Mongols conquer the whole country and violently eliminate the whole family.
 
That is within the context of a full blown civil war (perhaps as a coup attempt gone wrong) launched by imperial family after Kyushu, or perhaps when the Mongol-Korean forces have already reached the gates of Kyoto (should they fail to convince Kamakura to surrender by then)

Since it was the imperial court who suggested to submit to Mongols in the first place, I think it's a reasonable assumption.
 
That is within the context of a full blown civil war (perhaps as a coup attempt gone wrong) launched by imperial family after Kyushu, or perhaps when the Mongol-Korean forces have already reached the gates of Kyoto (should they fail to convince Kamakura to surrender by then)

Since it was the imperial court who suggested to submit to Mongols in the first place, I think it's a reasonable assumption.

Did the court realize that submission meant acceptance of occupation? If they did, then I could see this happening. If, more likely to me, they thought of submission as a tributary status a la Korea and China, then I don't think they would give up so easily.

Also, the Emperors can abandon Kyoto. It would be a loss of face if the Bakufu orders them to leave for Kamakura too, but I wouldn't think it's impossible. With little or no independent power base, it's not like they could choose to stay behind. As for a coup attempt, it is possible, but it didn't happen historically until disputes regarding the imperial succession got really bad, and I'm not convinced that the retired Emperors (the ruling Emperor at the time was a nobody) were ambitious or brave enough to pull this off.
 

scholar

Banned
1) Japan decides to surrender after the fall of Kyushu.
Never.
2) Japanese civil war between Kamakura and Imperial Court will follow the fall of Kyushu, which will certainly be exploited by the invading force.
About as likely as the Communists and Nationalists committing all their resources in their civil war against each other when the Japanese are invading. Or rather, about as likely as the initial burst of the German Blitzkrieg to go from Germany to Kamchatka before winter.

Some fighting is possible, even likely, but the Japanese will band together against a genocidal barbarian invader rather than continue their own little wars [on a large scale] after the first few cities are sacked, let alone the entirety of Kyushu.
3) Japan remains united in resistance to Mongol-Goryeo advance.
Yes, but... hm... There's a 'depends' here, but for the most part yes Japan would remain united.
 
This could also keep Korea more open, having a strong naval tradition develop would be good for Korea. On the other hand a long Japanese war would be real drain on Korea, but better that for Korea than something like the Imjin War...
 
Some fighting is possible, even likely, but the Japanese will band together against a genocidal barbarian invader rather than continue their own little wars [on a large scale] after the first few cities are sacked, let alone the entirety of Kyushu.
Yes, but... hm... There's a 'depends' here, but for the most part yes Japan would remain united.

Maybe a civil war might not happen while the Mongols are actually invading Kyushu. However, I think you underestimate the human capacity to do stupid things at the worst time. The Jin underwent their own succession struggles and civil wars just when they should have been banding together against the Mongols, so I really don't think it's impossible for a civil war. Just unlikely, mainly due to the fact that one side in such a civil war would hold essentially all of the military power.
 

scholar

Banned
Maybe a civil war might not happen while the Mongols are actually invading Kyushu. However, I think you underestimate the human capacity to do stupid things at the worst time. The Jin underwent their own succession struggles and civil wars just when they should have been banding together against the Mongols, so I really don't think it's impossible for a civil war. Just unlikely, mainly due to the fact that one side in such a civil war would hold essentially all of the military power.
About as much as I underestimate the ability for the Soviets to muddle up their defenses so much that Barbarossa will make it to Kamchatka, or that the Chinese civil war will continue to devote most of the resources against each other rather than fight Japan, currently invading and taking over most of the populated regions of the state.

The Jin has its own very messy problems, succession troubles being merely onw of the factors. With Japan this doesn't happen, and wouldn't. The factors aren't there and the cultural cohesion of the state is far more solid. Political cohesion? no. Cultural? yes.
 

Hmm. Considering that that particular post (assuming that it's recent) got you more interested in Korean history suggests that I haven't been putting enough effort into the process of updating my timeline so far, but that's that.

Anyway, I'm assuming that Sumeragi made that post based on how you obtained that from an anime website, along with the fact that the points made seem to resemble the ones that she made earlier on this website. I think the analysis was more geared toward the fact that it would have been possible for a Mongol/Korean presence on Kyushu, and have some limited influence in Shikoku and the southern area of Honshu, although other areas in Japan would mostly be left unaffected due to geographic barriers. In terms of trade, the inhabitants located on the Korean peninsula and Japan had traded actively for almost a millenium before the Mongols invaded, although the frequent wokou raids beginning around the early 13th century led to an unstable relationship. In other words, the economy would not be significantly affected unless the wokou could be completely butterflied away by the late 13th century and not reemerge for at least three centuries or so.

In addition, the first scenario would be extremely unlikely, as WhatIsAUserName pointed out earlier, because there would be no real impetus to conquer Japan. The Mongols attacked Goryeo for almost 40 years, starting in 1231, continuing through six campaigns, and although the latter nominally capitulated in 1259, revolts continued to occur until 1273. For comparison, the war with the Southern Song occurred from 1235-79. The main reason for the numerous campaigns was mostly because they were afraid that the Koreans would stage raids in order to disrupt supply lines and coordinate military tactics with the Southern Song, but Japan was geographically insignificant, relatively speaking. I don't know enough about Japan to assume whether the two later scenarios could occur, but my assumption is that regardless of the situation, because the Mongols would not be used to the terrain, although they would probably adopt somewhat, it would be hard for them to advance much farther than Kyoto.

After Kyushu is conquered, because the Yuan will eventually almost certainly disintegrate, there will be contention between Korea and Japan over the island, but in order to predict the butterflies, the possible details and logistics for the invasion must be worked out beforehand.

Keep in mind that the late Koryo royal family and many noble families became pretty Mongolized due to lots of intermarriage and Korean princes often staying in the Mongol capital.

True, but Goryeo was unique in that it was the only state that retained its monarch after it surrendered to the Mongols. Vietnam is a possible exception, but it was less influenced by the Mongols due to geography. Also, the relations went both ways, as members of the Mongol royal family also married people from Goryeo.

Again, the Kamakura Shogunate is unlikely to accept being tributaries of the Mongols, and the imperial family probably wouldn't accept such a subordinate status. After all, about 700 years before the Mongols came, the Japanese Emperors already thought of themselves as equals with the Chinese ones.

I see your logic, although comparing two situations 700 years apart doesn't exactly make sense. The Nara and Heian courts actively adopted Tang customs, and when the Japanese captured those stranded after the Mongol invasion, they executed everyone except for the Chinese. However, your general point still stands.

This could also keep Korea more open, having a strong naval tradition develop would be good for Korea. On the other hand a long Japanese war would be real drain on Korea, but better that for Korea than something like the Imjin War...

Yes, but Korea continued to retain strong naval traditions for more than a millennium until Joseon was founded in 1392 and adopted Confucianism, causing the military to decline. In order for Korea to retain a standing navy, the government's viewpoint of corruption stemming from Buddhist temples would need to be butterflied away, or another "open" ideology must be firmly entrenched in Korean society by the 15th century, which would almost certainly require a pre-1100 POD. The Imjin War did cause the navy to be briefly revived, but it also disintegrated soon after the Japanese withdrew.
 
I see your logic, although comparing two situations 700 years apart doesn't exactly make sense. The Nara and Heian courts actively adopted Tang customs, and when the Japanese captured those stranded after the Mongol invasion, they executed everyone except for the Chinese. However, your general point still stands.

Oh, I meant that, the Japanese Emperors considered themselves to be equals to the Chinese Emperors since 600 CE. Their title for themselves, tenno (天皇), can mean "Heavenly Emperor" and probably came about as a title equal to both tianzi (天子) and huangdi (皇帝) That's why I don't think it's likely for the Japanese rulers to accept subordinate status to anybody, not even the Mongol khans.
 
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