Lords of the East: Korea, China, and Japan
The Zeng had not taken kindly to the Korean occupation of the Liaodong Peninsula. Given their insistence on restoring all of China to native Chinese rule, having even a small corner still controlled by foreigners was unacceptable, even if said foreigners were Koreans and not the typical steppe or forest nomads. Ancient Korean claims dating back to Goguryeo and Balhae were dismissed.
Furthermore, the Jurchen were an issue. Given Jurchen history during the years of the Song dynasty, the Zeng were very keen on being the ones dominating the Jurchen clans. Having the Koreans be the paramount power in the region was also unacceptable.
The Zeng wanted the Liaodong Peninsula back, primacy in the Jurchen lands, and the Koreans to retreat back across the Yalu and become Chinese tributaries as they had been in the past. That was the proper relationship between Korea and a China that was going to restore the fullness of Tang. Gao Qiyu, the Jingtai Emperor of Zeng China, did not expect much of a fuss from the Koreans given the promise of frequent tribute missions (which served as a guise for trade) and subsidies to support Korean students who wished to study in China.
King Danjong of Korea however was not much interested. Coming to the throne in 1630 at only nineteen, he is continually conscious of falling in the shadow of his father, already known as Sejong the Great. Towering in physique as well as ability, Sejong had overseen the conquests in the north while presiding over a prosperous heartland. (The tenant farmers and nobi locked into a life of backbreaking labor with no prospect of relief might take a lesser view of Sejong, but nobody who actually mattered would’ve troubled themselves to ask their opinion.)
Danjong is physically smaller than his father was along with a weaker, more easily influenced, personality, which can’t help but fuel already extant concerns about inadequacy. Fighting against those feelings, Danjong was loathe to give up his father’s and predecessor’s accomplishments. The resumption of the highly profitable trade missions to China, which have been in abeyance for decades, is most desirable, and if the Chinese wish to call it tribute Danjong and the yangban are fine with that. However he is not willing to give up Liaodong and the Jurchen primacy, which Luoyang demands before receiving any missions.
Fueling his resistance is a contempt for Chinese military prowess, an attitude he is far from alone in having. The Koreans had thrown off their foreign yoke decades ago, far earlier than the Chinese, and with substantially less difficulty. While China was getting hammered by the peoples of the north, the Koreans were subduing the Jurchens to their north. Given recent Chinese performance, the Koreans see little to fear from Zeng wrath. (A counterargument, that Korea was an afterthought to the Tieh and Later Yuan while China was the main event, is ignored if it is even imagined.)
The Jingtai Emperor had been most displeased at the Korean rebuff and in 1634 sent an army of 10,000 men to the Korean Liaodong. Given its relatively small size, the Chinese aim clearly wasn’t to conquer the peninsula outright, but it breached the frontier as a show of force. The aim was to assert Chinese claims and to unnerve the Koreans into giving way. The effort backfired however when the Korean governor attacked the Chinese interlopers and drove them back to Chinese territory with heavy losses.
The Emperor was now utterly incensed, along with the whole Zeng court. It wasn’t just that the assertion of rightful Chinese claims had been met with violence, although that was bad enough. It was that a substantial portion of the Korean army had been comprised of Jurchen soldiery; the Koreans had dared use loathsome nomads against the Middle Kingdom itself. In the atmosphere of the Zeng court, where the wound of foreign, particularly nomad, domination still was raw, Korean actions were acid in that wound. The Koreans had unwittingly conjured up the Chinese nightmare while the memories were still fresh. In the Zeng court, it was no longer about the Liaodong or putting Korea back in the tributary system, it was a matter of breaking Korea as a threat to the Celestial Empire.
In 1635 a much larger army, with the most conservative estimates starting at 100,000 men, invaded the Korean Liaodong. Despite sharp and bloody fighting, the heavily outnumbered Koreans were quickly ejected from the region with the death of the Korean governor who had fought the 1634 battle. His replacement was Kim Cheon-Il who reorganized the battered Korean army units and parried Chinese efforts to breach the Yalu River line.
Despite his success, Kim Cheon-Il was greatly concerned. He was heavily outnumbered and his spies reported more Chinese reinforcements entering the theater. Thus Kim Cheon-Il was constantly sending messages to Seoul requesting reinforcements of his own, while also recommending that Korea cede the Liaodong to China.
Kim’s communiques did not go down well in Seoul, where the royal court saw things substantially different from Kim’s command tent. They still believed in the automatic military superiority of the Koreans over the Chinese; Kim’s highly successful defense of the Yalu despite the numerical odds was proof of that. The earlier defeat in Liaodong was blamed on the governor being complacent after the 1634 victory.
Now if Kim had been requesting reinforcements so that he could go on the offensive and retake the Liaodong, the King and Court would’ve understood and heartily approved and supported such measures. However despite several pointed references in Court missives sent to Kim, the general is clearly still looking to remain on the defensive. That he then suggests capitulating to the Chinese, abandoning all the work of Sejong the Great after just one reversal, is the last straw for King Danjong. Kim Cheon-Il may have had his moment, but clearly he has lost his spirit and needs to be replaced with a leader with more drive.
The choice of replacement is Won Gyun, who has long had personal grievances and rivalries with the Liaodong governor and Kim Cheon-Il. He was incensed when the latter was picked instead of him to command the army but since then he has used his position at court to steadily undermine his rival. Certainly Kim’s missives and recommendations haven’t helped his standing in Seoul, but Won has been exploiting them as much as possible, bending the King’s ear. King Danjong is most happy to hear that the problem is only the character of the commander.
Kim Cheon-Il is recalled to Seoul in disgrace and is replaced by Won Gyun. Originally Kim Cheon-Il was supposed to be executed for defeatism but he has supporters of his own at court and is instead demoted to a common trooper.
Shortly after Won Gyun takes up his new command, the autumn rains commence and turn the landscape into a sea of mud, making an offensive impossible. Nevertheless Won is champing at the bit to go onto the attack. Having condemned his predecessor for staying on the defensive, he can hardly do the same, particularly as Kim is still around and available to be reappointed. As soon as the winter freeze is in, hardening the ground, he marches northwest into Liaodong. He attacks with the bulk of the Korean army, reportedly 60,000 strong.
Opposing him is another general new to the scene, the previous Chinese commander having been replaced (although not executed) after the repulse on the Yalu. Li Rusong is a veteran Zeng commander, experienced in warfare from the re-conquest of Northern China. From Tieling in the borderlands between pre-war Chinese and Korean territory, he is much more aware of Korean attitudes vis-à-vis the Chinese than his predecessor, his awareness complemented by a vigorous and successful intelligence-gathering operation over the autumn. Aware of Won Gyun’s machinations and the strategic implications thereof, Li sets his own plan into motion as Won advances.
The Koreans face little resistance as they march over the frozen landscape, combat limited to minor skirmishes in which the Chinese give way after a short bout. Won is pleasantly surprised at the ease with which he forces the Qian Mountains, a Chinese force mustering for a serious battle but giving way as quickly as in earlier encounters. It seems that all that was needed to scatter the Chinese was a proper vigorous display of Korean martial prowess.
Descending from the mountain passes, the Koreans enter the Liao River plain, where their first impediment is the fortified city of Anshan. Won sets up a siege although it is impossible to dig trenches in the frozen ground. That matters little as Li Rusong marches up from the south to finally offer battle in earnest.
The battle proper begins on February 5, 1636. Won is eager for battle, preferring that to a long and difficult siege, especially as it appears that he has a slight numerical advantage. Spreading his lines, Li Rusong matches, but with his inferior numbers there is a clear weakening of the Chinese center where Li’s banners fly prominently. Charging forward, the Koreans push the Chinese center back, bending it but crucially not breaking it.
At which point Li Rusong springs his trap. The Chinese wings, reinforced and largely unmolested, pivot inward, slamming the Koreans from both sides. Suddenly pressed on three sides, it is not long before the Koreans rout and break for the rear. There is still an opening there but the Koreans are savaged before they flee the kill-zone, flying back to their original camp.
Li Rusong doesn’t follow up with an immediate attack on the camp as sunset is drawing near, but the Koreans, concerned about being trapped between the Chinese army and Anshan Citadel, retire the next morning, having to leave behind much of their baggage to move faster. Li follows, harassing their line of march, but makes no attempt to force another pitched battle.
The reason why becomes apparent as the Koreans reach the Qian mountain passes. The reason Li’s army was so small was that he’d sent men to block the passes. As the Koreans attempt to break through, the Chinese guarding the passes attack from above as now Li pitches into their rear. Crazed panic grips the Koreans.
It is complete carnage. The Korean retreat is blocked by a palisade, and with their loss of baggage and artillery at Anshan they have no easy way to blast through the barrier. Those climbing it are shot down in droves by Chinese archers and arquebusiers. Those who make it then tumble into a ditch dug, sometimes with explosives, on the other side. Only once enough broken and dying bodies have filled the ditch can others clamber safely onto the other side, only to discover to their horror an identical obstacle and bloody gauntlet. Few made it through the first; less make it through the second.
It is a complete and utter disaster, of a scope rarely seen in military history. According to the Koreans, only 1 out of every 12 men who marched out with Won Gyun ever return to the lands south of the Yalu. Won Gyun is not one of them. Accounts of his death vary, some saying he died valiantly, sword in hand. Others say he was trampled to death by his own soldiers or died in one of the ditches from falling. At a stroke Korea’s regular army has been effectively annihilated.
This time Li Rusong does not hesitate to press his advantage. Moving forward, he marches across the Yalu, where the water is frozen thick enough to support artillery. In his race, he arrives at Pyongyang with only 25000 men, the remainder straggling up the road, but surprise and shock more than make up for his lack of numbers. The city falls after only two days; Trooper Kim Cheon-Il is one of those killed defending the battlements.
After Pyongyang, Li Rusong halts his advance to bring up more troops and supplies, with worsening weather putting a halt to further winter campaigning. But the Zeng court, ecstatic with the success, is already organizing Liaodong as a Chinese province and making plans to turn Pyongyang into the base of a Chinese commandery to oversee the region under Chinese hegemony. Preparations are made to send more reinforcements to Li Rusong to support new operations in 1636 aimed at bringing all of Korea into obedience to the Middle Kingdom.
As winter wanes, war waxes in intensity. Despite frantic recruitment efforts, the Korean army is still woefully understrength and under-equipped to face the Chinese juggernaut. Still the Chinese are not having everything their own way. Resourceful yangban are gathering ‘Righteous Armies’ of peasants and leading them in guerrilla attacks on Chinese detachments and outposts. The great monasteries are rallying their monks and leading them in raids as well.
King Danjong, now terrified of losing it all, also appeals for aid outside of the Land of Morning Calm. A Korean embassy arrives in Osaka, begging for aid in the court of the Shimazu Emperors.
Shimazu Yoshitaka, second of the dynasty to rule all of Japan, has only been on the throne for two years at this point. While the daimyo seem largely pacified, that is not something that can be assumed. A campaign in Korea would do wonders in keeping them occupied. More importantly, the Shimazu are extremely alarmed at the possibility of Korea being in Chinese hands. It would be a dagger pointed directly at their own domains, and given their history of piracy, the Chinese have many grievances against the Shimazu. Plus the Japanese cannot forget the great armadas that were sent against them by the Yuan that were only beaten by the divine winds. Given that Zeng China seems to be acting extremely expansionistic here, there is much concern in Osaka that the Zeng will try and emulate the Yuan once Korea is pacified.
So the Japanese respond vigorously to the Korean call for support, Yoshitaka pledging to send an army by summer, although a small expedition of 4000 is sent to Busan just a few weeks after the agreement is made. Yoshitaka meanwhile sends an embassy of his own to Pyrgos, requesting the Katepano send aid as well, although the request is of the ‘will not take no for an answer’ type.
The Katepano complies with the request. While the Chinese element makes up the largest portion of the traders in Pyrgos, the Japanese are also extremely important. In addition, all the Katepanoi of the east have clear instructions from Constantinople to stay on good relations with the Japanese. Their common Orthodoxy is a part of that missive, but it is clear to both the White Palace and the Katepanoi that good relations with the Japanese are crucial to Roman strength in eastern waters.
The Katepano does not provide ground forces. Yoshitaka does not need them; he is drafting plans to mobilize and send as many as 150,000 men to the Korean peninsula. [1] What the Katepano provides are warships. The Japanese have many vessels of their own, for trade and transport, but they have relatively little in the way of heavy warships. They were not needed in the campaigns to subdue and pacify Japan and wokou raids were done mainly with lighter and faster vessels.
Thus far all the fighting has been on land, but naval warfare will be critical in the campaigns to come. The size of the Chinese forces invading Korea mean they are dependent on seaborne supply routes, as will any Korean-Japanese armies moving to oppose them. Furthermore, the Chinese are soon aware of the alliance and know that cutting the maritime link between Korea and Japan would be a major blow against their enemies. Whoever controls the Yellow Sea will almost certainly win the war.
The Katepano of Pyrgos sends two fourth-raters and three fifth-raters, a quarter of the Romans’ big warships in the east, along with more vessels provided by Ship Lords with Japanese trade connections. There are also numerous light warships, including those that came from the Caribbean by sailing around Terranova and across the Pacific. [2] Leo Kalomeros will get his share of action as the Roman and Japanese naval contingents sail to reinforce the Korean fleet, now under a new commander, Yi Sun-sin.
[1] The Japanese invasion of Korea in 1592 IOTL at the start of the Imjin War was that big.
[2] For the Katepano of Pyrgos, the Spanish threat is minimal while keeping the Japanese happy is paramount.