Waterwheels, Threshers, and Japanese Trade
The Shōni clan ***
I've already introduced Arabic numerals and basic arithmetic here. I thought it was simple, but it seems like no small matter.
Because when I went to see just how tough his job was, his office was piled high with scrolls.
"To be honest, I'm handling the work of dozens of men all by myself right now. I do have subordinates, but there's still too much on my plate at the moment."
Hmm, yeah, that makes sense.
"Ahem. Understood. How can a man be so narrow-minded? Still, tax officers like you earn your keep with results, don't you? Look at those hundreds of waterwheels. See how they're drawing out that wire using the river's force? We can apply this to all sorts of things, right?"
It's not just human muscle—it's the power of water producing goods. Nothing hard about this level of tech, is it?
"Machines like these must be rare even in Song. But you're saying this will change the country on a grand scale?"
"You've seen the manure soil, so you know. It's great for roads, and it can improve city hygiene too. And with this wire, we can do all kinds of things. I've got a plan laid out."
Pipework is new to me, but I'll give it a shot this time.
"So you're going to try it here in Yoyang. Why not Gaegyeong?"
Because Gaegyeong and Yoyang are different in difficulty. Gaegyeong's been the capital for 300 years, so it's not ideal for experiments. We could build a new city in Seogyeong (Pyongyang) and move the capital if it succeeds, but developing Yoyang—facing the Mongols and handling steppe trade routes—makes more sense. That way, the Jurchens and Khitans in Manchuria will see we're looking out for them.
"Gaegyeong's the 300-year capital, and the terrain makes it tougher than Yoyang. We need real-world experience here first."
"Understood."
The craftsmen are a bit short, but I think we can manage. Just one solid push. But before that, something else to handle.
To lock down sea routes, it's time to extend influence to Japan. And while we're at it, grab a firm hold on their territory.
"Uncle. One favor, please. Can you lend some strength for this pretty niece of yours?"
So I sought out my uncle, Jeongan.
"Hahaha. As the Military Regent, of course I'll help. What do you need?"
"Could you go as chief envoy to Dazaifu in Japan?"
Even if we wanted to conquer Japan by force, we'd lack justification. So instead, we'll wield diplomatic influence. What if we offer investment rights even to Japanese clans like the Shōni?
Dazaifu, Japan
Around this time, gifts from Goryeo arrived in Kyushu, Japan as well. Among the recipients was the influential Shōni Sukeyoshi of the Shōni clan.
Shōni Sukeyoshi had succeeded his father as the head of Dazaifu—the regional administrative office in Chikuzen Province, Kyushu—and took the title of Dazaifu Shōni (Deputy Intendant of Dazaifu). He even made Shōni the family seat. In original history, he handled Mongol envoys and fought in Yuan's invasion of Japan.
Before this Shōni Sukeyoshi, the Goryeo envoy presented gifts as usual—but these were extraordinarily lavish.
"These are the items our Goryeo presents to the lord."
Jeongan, the chief envoy, explained each one: soap, ginseng, pepper. Even glassware. Truly luxurious.
And beneath the luxuries lay sharkskin leather.
Shōni Sukeyoshi stared in awe for a moment, then shook his head.
"Heavens, the Goryeo general truly bestows all this—ginseng, soap, everything—upon us?"
Not to speak ill, but this was practically tribute. Goryeo was a great power compared to the Shōni, but the sheer volume felt odd.
Yet the Goryeo envoy only smiled faintly.
"Indeed. So please continue cracking down on the wako pirates."
"But isn't Goryeo strong enough? Why need such pirate suppression?"
He'd heard Japanese traders to Goryeo rave about their massive trade ships. Surely that handled wako fine? Pirates weren't that formidable anyway.
"We can't exclude even small variables. Our trade brings in vast wealth—these very items are fruits of it."
The Goryeo official declared confidently before Shōni Sukeyoshi.
This piqued Sukeyoshi's curiosity about Goryeo's trade methods. Wallrand Island trade alone couldn't yield such hauls.
Seeing the bait taken, the Goryeo envoy showed the keeled ships docked at Dazaifu's port.
"Oh! How do you build such huge vessels? I heard Goryeo clans are powerful—can you manage this?"
"It's a national project. What can the clans say? We even take their 'investments.' They fund the ships with their wealth, then get priority on trade goods from those voyages."
"Priority? How valuable is that?"
"Take spices from Taishi—too expensive, right? But Goryeo now sails directly there, buying pepper cheap in bulk. We allocate some to investors at priority or dirt-cheap prices."
"Ahem. We're recipients of your gifts—could we join in?"
Sukeyoshi suddenly wanted in. Seeing Goryeo goods, he'd grown envious. Especially those massive ships.
"Possible, but... we're already building plenty. How about something else?"
"Something else?"
"Clans don't just fund ships—they offer local specialties. Things to provision the crews, that sort."
"Speak plainly."
"I've heard Kyushu produces sulfur, cinnabar (mercury ore), copper, camphor trees. Hand those over—exclusively to Goryeo."
"Even so, that's tough."
Huge profits for the Shōni, sure—but he lacked exclusive rights to Kyushu's resources. He could if pushed, but eyes would watch.
"Why? Doesn't the Shōni clan wield strong control over Kyushu? You lead gokenin, manage administration, inspect our or Song ships first. You dominate trade routes, no?"
Flattered, Sukeyoshi felt his shoulders rise but kept his face straight.
"Still, other clans have spheres here."
"If the Shōni, trade managers, blockade ports—what's the issue?"
"Blockade ports?"
He'd never considered it. But it sounded plausible. With his Kyushu sway, why not? Administration was in Shōni hands.
"Block foreign trade for other clans, tax them heavily to detour through you. Secure monopoly rights. Or safely act as massive relay merchants, claiming those clans' shares for Shōni. Think long-term."
"Long-term?"
Sukeyoshi perked up. Pure temptation, but Goryeo officials were eloquent—sure to dazzle.
"Sell priority goods across the islands, not just for clan use. Shōni gains immense wealth and glory, right?"
Exactly. Not just Kyushu—spread to all Japan. Success could mean Kyushu independence or shogunate voice.
"Not bad. Very well, I'll try."
"We'll petition our lord to issue Shōni a priority gold plaque."
The plaque proves priority holder status. Lord? Goryeo had a shogunate-like system.
"Your lord?"
"The Choi clan lady, war hero who beat the Mongols. Now Military Regent as successor. She's behind this investment policy too."
"Ho, impressive. Even Goryeo's shogun women are formidable."
Mongols threatened even Zhongyuan—yet a woman crushed them? Briefly, he wondered if Goryeo was weak, ruled by a woman, Mongols overhyped.
But those giant ships, crushing clans with priorities—no ordinary folk.
This deal meant her—their lord—as backer. With the plaque, Shōni ties to Goryeo, building power beyond Kyushu, even against the shogunate.
Resources? Trivial to give.
"Then this envoy withdraws. Must report details swiftly."
"Do so. Until next time."
Thus, half of Choi Yeon's goal was achieved.
On a whim, thresher development began too.
Install a cylindrical device on flat ground, lay cloth behind or below. Step the pedal rhythmically with one foot; gears turn a drum studded with wire pins at high speed.
When the drum spins right, grip rice or barley sheaves tight in both hands, press just the heads against it—grains shower down.
Yeah, you get it. A manual thresher was invented. Not engine-powered—just manpower.
This alone eases farmers' toil. Plus, a foot-pedal flail alternative: the holt, using traditional winnowing.
Teeth-like blades hold grain; step the wooden pedal to fix it, insert stalk base, pull toward you gripping the straw—comb catches, grains fall below.
Holt takes effort, but handy alongside the thresher.
"Wow, it really separates grains like this."
"Incredibly convenient. Even women and children could use it."
"Order the Treasury to distribute to local offices for farmers to borrow. And announce I invented it."
"Winning farmers' hearts, eh?"
"Obviously. I'm to rule this land—public support is a given."
"Understood."
Farmers will praise the Choi. The Wang are symbolic like Japan's imperial house; Choi regime thrives on authority and acclaim.
Goryeo-style cokes steel mills recently completed too. With Japan's Shōni clan, we've locked in cinnabar (mercury ore), copper, camphor trees—exclusive.
Investment? We're sucking their resources, giving luxuries in return.
Strategic stuff—not to pass up. Mercury for gold mining, detonators. Copper? Obvious—currency, ship sheathing, wires, brass.
Camphor trees? Chemical spice. Extract white camphor crystals for smokeless powder stabilizer, early plastics. Even meds.
Of course, I can't whip these up overnight. It'll take time. Lots of it.