Yi Bang-won Appoints Min Mu-jil as Minister of Military Affairs
When I went to the Hwatong Dogam, there really was a matchlock gun. To be precise, it was an early matchlock—an archetypal arquebus. I'd originally tried to make a musket, but failed every time. The reason was a lack of technology. The ones I built were ridiculously huge. There was no way anyone could fight while carrying something that big. Sure, exploding barrels were a problem too, but the size was the real killer. Come to think of it, early muskets were so large they needed a stand. They only got smaller as the tech improved. So I'd pivoted and made this instead—and it worked. It was a step beyond the primitive hand cannon, though still basically an early arquebus. That thing was just a hand cannon with a trigger slapped on; this at least looked like a proper gun.
"Is this it?"
"Yes, my lord."
I told them to fire it, and they loaded it exactly as I remembered from history. I even took a shot myself. It was definitely the matchlock gun I knew.
"How did you solve the barrel problem?"
Yi Cheon-u pointed at Jang Yeong-sil. "This boy figured it out."
Oh! So Yeong-sil really pulled through.
"How exactly did you do it?"
Jang Yeong-sil explained that instead of just pouring it into a simple mold, he'd mixed wrought iron and steel into plates, hammered them, and rolled them into tubes. Whoa, so that's how it's done. True geniuses transcend eras.
"You did exceptionally well."
Putting Jang Yeong-sil here was the best decision I'd made. Now that we had the matchlock, we'd met the bare minimum requirement. With practice making guns, our skill would improve, and eventually we'd craft usable muskets. Later, we could develop flintlock muskets. It'd take time on the optics, but it was feasible. Flint originally referred to siliceous rocks before it meant flint stones, and Joseon had plenty of quartz—the prime example. With good smelting, it'd work. Worst case, we could import pyrite during southern expeditions. From then on, Joseon's military power would be on another level.
I lavished praise on Jang Yeong-sil, then headed to tell Yi Bang-won about the weapon. My steps were light. This was the best news I'd heard lately.
When I reported to Yi Bang-won, he said, "A new small arm, eh? I'm intrigued. Can we go see it now?"
"Of course, Your Highness."
I took him straight to the demonstration ground and fired it myself. A hole punched right through the target board Yi Bang-won had been using for archery. But his reaction was like he'd seen a ghost.
He asked how fast it could fire, and I said it was slower than a bow. But when I added that training time was far shorter, he nodded and praised it as an excellent weapon. It would cut the cost of training skilled archers, he said. That was the main reason guns displaced bows historically—the training time was drastically less.
But Yi Bang-won's reaction wasn't quite what I'd expected. He kept praising me, sure, but I thought he'd be jumping for joy.
"We should show this to all the civil and military officials first. They deserve to share the good news."
"Your Highness, give me a month. If I train them to hit targets by then, the officials will be even more impressed."
He nodded and agreed. Hmm, his reaction's a bit underwhelming, but he did say it was good. And he seemed pleased enough.
Meanwhile, back in his private chambers, Yi Bang-won asked the eunuch, "Is there a scribe in the chambers?"
"No, Your Highness. Ever since you exiled Scribe Min In-saeng, none have come."
Reassured, he dismissed the eunuch. Once alone, he burst into laughter, overjoyed. He'd held back his excitement in front of Min Mu-jil because of all the people around. He couldn't risk losing face in public—especially after the Min In-saeng fiasco. That's why he was celebrating solo now.
Yi Bang-won loved the matchlock gun. Its power was impressive, but what thrilled him most was that it was made purely with Joseon technology and local materials. Joseon's staple weapons—cannons and composite bows—relied on imported copper from Ming or Japan for cannons, and water buffalo horns for bows. But this matchlock could be made entirely in Joseon, freeing them from Ming meddling over weapon materials whenever they bolstered their forces. That made him ecstatic. Things were calm now, but Ming could turn prickly like in Zhu Yuanzhang's day anytime.
"I must use Mu-jil even more."
Min Mu-jil enjoyed unparalleled favor from Yi Bang-won, seen as a merit beyond merits in court. The Office of Censors acknowledged his talent but petitioned that the favoritism went too far. Yi Bang-won ignored them. This matchlock success only confirmed his trust was well-placed.
In any case, Yi Bang-won resolved to appoint Min Mu-jil as head of the Ministry of Military Affairs. He planned to strengthen the Six Ministries at the expense of the State Council. They'd shifted from the old Ruling Council to the State Council, but it still held too much power. Especially, he aimed to boost the Ministries of Personnel and Military Affairs. For the latter, with military administration plus command authority transferred from the disbanded Bureau of Military Affairs, the role demanded absolute trust. He'd agonized between veteran Nam Jae and Min Mu-jil, but this sealed it for Min Mu-jil.
As Yi Bang-won pondered personnel reforms with Min Mu-jil as Minister of Military Affairs in mind...
While Yi Bang-won mulled over reforms, Min Mu-jil stayed swamped. Hunter training, Left Army Commander duties, and lessons from Yi Seong-gye left no time for new foods.
"When will you bring new dishes, you rascal?!" Yi Seong-gye grumbled, gnawing a chicken leg. He loved chicken.
"I'm truly busy, Retired King. The new weapon development left no choice."
"Is it? Not another powder-hungry fire wagon, I hope?"
Opinions on fire wagons had soured lately. Great performance, but too powder-intensive. That's why this matchlock demo was crucial—it used less powder and excelled.
Yi Bang-won had played it cool before me for decorum, I'd learned later from Min Da-yeon. Alone with her, he'd been ecstatic. Min In-saeng's trauma lingers, huh? It's been ages since the exile, yet...
Anyway, time to reply to Yi Seong-gye. "You'll like this one."
"Good. If not, you're done."
Bring it.
A month later, July 16th. Yi Bang-won summoned all officials. I handed matchlocks to my trained gunners and had them assume firing positions.
"All squads, prepare to fire!"
They loaded—over 20 seconds, but solid progress.
"Fire!"
They aimed and fired in unison. The roar startled the officials, but they quickly checked the targets. Their faces were priceless—mirrors of Yi Bang-won's earlier shock. Holes riddled the wooden boards.
"Such power from a small gun..."
Ha Ryeon looked ready to faint. Then Kim Sa-hyeong asked, "Left Army Commander, what is this weapon?"
"It's called a matchlock gun."
I explained its pros and cons. "These gunners trained for just a month under me. That's possible with one month. It's the matchlock's greatest strength."
Suddenly, Yi Seong-gye chimed in. "An incredible weapon. Beyond expectations."
Why's he here?
"No complaints left—it's that good."
His reaction was refreshingly positive. It sparked widespread awe. "Truly remarkable." Civil officials were especially thrilled—no more buffalo horn obsession. The court planned southern buffalo farms for self-sufficiency, but imports were burdensome. Self-reliant weapons scored huge with budget hawks. Lately, the Office of Censors griped about Yi Bang-won's military spending; this solved it.
Nam Jae added, "Your Highness, this is revolutionary. Reward them greatly."
Yi Bang-won beamed and promised lavish rewards for the artisans—plus something special for me later. He called them forward, asked names, and bestowed grain on each as I recited their merits. They were overwhelmed. Jang Yeong-sil beamed too. Being remembered by the king was the ultimate honor here.
I wonder what my reward is.
Then Yi Bang-won said, "Seeing this matchlock gives me an idea."
What now?
"I've long pitied the people suffering tiger attacks. I considered tiger-hide constabularies, but now we'll use matchlocks against them."
Tigers were a plague this era. Late Goryeo's invasions aside, they were constant worry.
"Inspector-General of Tiger Hunts Senior General Sim On and Commander Min Mu-hul."
"Yes, Your Highness."
"Arm your hunters with matchlocks, hunt tigers in Gangwon Province, and ease the people's fears. Spare no expense."
"Yes, Your Highness."
Sim On and my brother Mu-hul? Yi Bang-won does favor Mu-hul. Only real post in the family besides mine, thanks to his humility. Shame—I wanted it for falconry excuses.
Afterward, Yi Bang-won talked more, ominously. He planned stricter military drills. Sounded like cover for personal hunts. His hunting passion was legendary. Still, more training was good—armies need it.
The demo wrapped up. Days later, Yi Bang-won assembled all ministers in the main hall for organizational reforms.
"In the early dynasty, following Goryeo precedent, the State Council oversaw the Offices, the Bureau of Equivalence managed currency and grain, and Left/Right State Councillors doubled as departmental judges, leaving the Six Ministries sidelined. Thus, I hereby subordinate the Bureau to the Ministry of Finance, transfer civil and military appointments to the Ministries of Personnel and Military Affairs. To prevent State Councillors from holding departmental judgeships, I appoint Ministers to head the Six Ministries, elevated to Regular Second Rank."
Yi Bang-won was finally empowering the Six Ministries. His hallmark was the Six Ministries direct governance system. This curbed old Ruling Council premiers' concurrent control, boosting independence. He outlined the full structure: Ministers, Vice-Ministers, Remonstrators, etc.—the classic Joseon setup I'd known. No more confusion.
Then: "The Ministry of Military Affairs shall wield administrative authority plus command rights from the disbanded Bureau. It shares command with the Three Armies Commander Bureau, but its head is the Minister."
Whoa, the Minister of Military Affairs has insane real power. Was it always this strong? It's basically all military authority in one man's hands.
Yi Bang-won announced the Ministers: "Nam Jae for Personnel, Yi Jeok for Rites, Yi Ji for Finance, Yu Yang for Justice, Han Sang-gyeong for Works."
Yi Jeok—Mu-hul's father-in-law—climbed high. Nam Jae, as expected, favored. But Military Affairs?
The core was Personnel and Military. "Finally, Min Mu-jil for Military Affairs."
Me? I'm the Minister? Was that the 'special reward'?