Post-War Maneuvers: The Border Rush
Probably, after receiving my letter, Ogotai must have been furious, and Yalu Choeje here had tasted hell trying to persuade him.
"You're not going to spout nonsense like returning to the brotherly relations of old, are you? I hope you thoroughly remind them that the cause of this war lies with your country. We love peace, so we've humored the Mongols to some extent, but it's now crystal clear to all under heaven that the Mongols are barbarians who know nothing of propriety."
At my words, Yalu Choeje's face twisted violently.
Aigoo. What good is that face from the man who worked so hard to reform the Mongols?
"I hope this isn't a seat for slandering our Mongols. How can you treat an envoy like this?"
Huh, feeling offended? But you lot started it first. If I were facing envoys from Jin or Song, I'd have welcomed them with a cute smile. But considering the outrages your Mongol envoys have committed in the past, they should be grateful for this much mercy. I think I've treated you plenty well.
Maybe I should soften my tone a bit now. After all, looking relaxed is more appealing than acting all tense and guarded.
"Let me say this upfront: if your state letter still uses emperor-state terminology pretending to be above us, you won't leave this land alive."
Japan had rejected Goryeo's state letters at first for the same reason. We just needed to apply it to the Mongols.
"What?!"
Yalu Choeje shot to his feet, but I kept my composure. Still, coldly, I drew my sword metaphorically and glared at him.
"The Mongol steppes may be vast, but how many more people do the Mongols have compared to us Goryeo? With barely under a million in population, do you think Goryeo looks laughable just because you're lording over some Han pigs in the Jin territories? Let me say it again. If that state letter is as arrogant as before, I'll send an army to the Mongol steppes on my own authority."
At my words, Yalu Choeje's hands trembled, and he let out a heavy sigh. He didn't seem to be continuing the probing accusations.
Alright, then. Time to ease up a little. Peace with the Mongols was necessary for us anyway. Father had promised the Jin envoys in Liaodong that we'd check the Mongols. We'd already given Jin some breathing room. We'd upheld our bond with Jin. The rest was up to them.
"There will be no more dismissive remarks toward your country, nor any emperor-state terms insulting you. It's merely for peace."
With that firm assurance, I sheathed my sword.
"Turning surrender into peace talks—quite the skill. Privately, I respected you for taming those barbaric Mongols, even setting up administrative organs to rule the Han."
"How do you know that so well?"
Here, I sowed a seed of doubt. Implying there was a spy near Yalu Choeje feeding info to Goryeo. What chaos might division breed?
"Goryeo's eyes are everywhere. Anyway, fine. As the governor of Yodong, I can't keep rebuking you forever. I'll open the road—head to Gaegyeong."
This much torment would do. I'd permitted the road to Gaegyeong at least. Who knew what they'd poke into on the way? They might snoop around.
"Assign escort troops on the way. We can't have them causing trouble."
"Yes, Governor."
And just like that, we couldn't let our guard down. The Mongols bowing to us was suspicious in too many ways. They might strike all at once after this show of submission. Until then, we needed household registers surveyed, armies bolstered.
"How's the household census from the capital coming?"
"Estimated at 3.5 million."
"As expected, thanks to increased agricultural output. They breed well too."
Goryeo's mainland had quite the population boom. No doubt because so many who would've been slaughtered by the Mongols were alive. Agricultural yields were nothing to sneeze at either. Still, paltry compared to the Central Plains. Even shrunken Jin probably had more. We'd need at least ten million minimum.
"Slave emancipation helped a lot. Of course, this excludes the Jin folk who migrated to the mainland—adding them makes about 3.6 million. Yodong's numbers aren't fully tallied yet, but I'd say around two million."
We'd have to add the Khitans on the Yodong Peninsula later.
"For now, Yodong's at two million, total 5.6 million."
If we outright seized all of Dongjin's lands, it'd hit six million easy. Hmm. I'd like to field 200,000 to 300,000 for expeditions. That meant needing more people. Early Goryeo had mobilized 300,000 for defense under total conscription, but overseas expeditions topped out at 170,000 for the Nine Northeastern Castles—and even that was returned. But with the population growth, I wanted more troops. And expand the elite Jurchen Byeolcho forces with real combat prowess. We'd held back fully embracing the Jurchens due to the Khitans, but now it was possible. Time to raise them into a mighty army under Goryeo.
"Preparing for war?"
I nodded at Kim Jun's words. Right—the war with the Mongols demanded constant vigilance. After two defeats, wouldn't they sharpen their blades for revenge? Not right now, at least not until they pushed west.
"The war with the Mongols isn't over. I always prepare for contingencies."
Goryeo's current field army, including Yodong and mainland, exceeded 200,000. With garrisons, 300,000 to 400,000. Insane for our population—a true military state. And we'd need more to defend expanding territories. Conquest was easy; holding was hard. That's our situation now. We'd rushed Yodong on perfect timing; if the Subutai war had gone poorly, we'd likely have lost it again.
"Contingencies meaning..."
"A cavalry force strong enough to strike the Mongol steppes. And troops to secure the Sixteen Prefectures."
That meant at least 300,000 to 400,000. So, swell the population too. Take in migrants, boost birth rates sky-high, breed the young men who'd die for Goryeo's future.
"Building military strength isn't impossible. But striking the steppes..."
Hitting the steppes was one option. If the Mongols threatened us while attacking Jin, we'd have to strike the steppes directly to disrupt them.
"Preempt their revenge. And if Jin falls later, we need the Sixteen Prefectures to check Song. You know what happened to old Goguryeo against Tang. To block Central Plains attacks effectively, we must intervene anytime and seize lands to threaten them."
The Khitans had milked the Sixteen Prefectures for ages. Goryeo needed that to profit via Song long-term. Ideally, keep Jin alive as a buffer—no need to take the Prefectures then. Grabbing them risked pincer attacks from Mongols and Song. Song had allied with us against Khitans and Jin before, but if we took that spot, things changed.
"Seizing the Sixteen Prefectures would force Song to check us."
"Can't ignore them, but taking them invites endless Song vigilance."
"Exactly. So Jin surviving is best."
If Jin fell, no skipping the Prefectures. Song's view of us was uncertain, but watch their Sinocentrism. We'd coexisted fine so far, but as we grew, we'd need to claim emperor status outright or revert to a unique monarchy like Taewang, equaling China. Lingering as a vassal would brand us in history as Chinese subordinates. Even in the 21st century, China and Japan mocked Korea as a Chinese tributary. Song would see Goryeo like Liao or Jin. Then they'd ally against us—with Mongols atop the Prefectures harboring grudges. Song proposes alliance? Mongols would bite. This era's Song wasn't sane, but still, the dynasty hyped as near-Industrial Revolution sans Mongols. Overhyped, really— their system had no need for machines despite tech and population. Plus Mongols. But Goryeo differed. With fewer people than the Plains, lay industrial foundations now for post-me growth—not full revolution, but base.
Best if Mongols ravaged Song max, retarding their tech—but that fattens Mongols. Bad for us. If Song rotted internally, perfect. Or whisper to Mongols to hit Song. If they barely hold without falling, Song bleeds huge. Looting Song yields riches. Wouldn't that ease our western push?
This much? Mongols knew by now conquering us their way was impossible, grudge or not. Realistic, they'd eye west if they couldn't hit us. They had spare capacity unless poking us more. A third war loss would end them for real.
"Then maybe we skip the Sixteen Prefectures?"
Great if possible, but no overt eyeing now. Plan variables. Worst case, fortify Yodong defenses ironclad, secure survival. Expand to Yoser max. Ogotai dying of rage-fueled illness would've sparked Mongol infighting—high odds—but the bastard seemed long-lived.
West it was, then. Even Mongols would wise up soon. While they begged peace, time for our schemes? Secure borders chance? Not just old Goguryeo—full Han ethnic survival to Yoser or beyond. No intent to invade China proper. Sixteen Prefectures was the limit; deeper, and Chinese numbers swallow Goryeo. For now, grab what we can. Their begging meant they needed breathing room. We'd claim up to our limit meanwhile.
"How many troops ready now? Mobile cavalry ideal."
I asked Kim Gyeongson, Yodong's horse-pasture overseer.
"Around 20,000."
"Who knows the future? With Mongol momentum broken, fix the borders now."
Poseon Mangno's remnants held vaster than Bohai lands. Consider Manchuria, sure. Same for us. While Mongols reorganized after 50,000 dead, secure the border at least. Perfect timing rush—what else? They'd thinned out militarily. Claim all lands Muqali's empire took in Yodong. Stake claims firm before peace.
"What if we meet Mongol troops?"
"We haven't made peace yet. Capture if feasible. Remember: the war's not officially over."
Scattered, not organized—our forces suffice. Don't overextend; just what we can hold.
"Secure at least to Yoser fully."
Grab it all before peace seals.