The military hospital named ‘義行院’ (Righteousness and Action Institute)[1] had numerous advantages in many aspects.

It was the ideal location for developing and improving various assistive devices, including prosthetic arms and legs. Additionally, while researching and developing various therapies for the rehabilitation of wounded soldiers, it provided significant help to those requiring rehabilitation in general society.

The institute also established a systematic foundation for studying the unfamiliar field of psychiatry while caring for and treating those who suffered psychological trauma and showed signs of mania from the horrific battlefield.

Lastly, it created a new profession by operating a large number of male orderlies to assist with tasks that might cause gossip if performed by women, such as helping disabled soldiers bathe or relieve themselves, as well as supporting rehabilitation therapy that required significant physical strength. In particular, male orderlies who received education at military hospitals and gained practical experience at the Righteousness and Action Institute were highly welcomed in medical settings dealing with trauma and burn treatment, as these areas also required many strong assistants, similar to rehabilitation therapy.

***

The battle that began with Zhu Qizhen’s invasion had a profound impact on the medical field.

It immediately laid the groundwork for significant advancement in trauma medicine. Military doctors accumulated experience and improved their skills while treating the flood of wounded soldiers that arrived whenever battles occurred. Furthermore, they discovered the need for research and improvements in areas that were either not mentioned in existing medical texts or were only vaguely described.

There was also substantial progress in improving surgical instruments for operations.

Until then, they had been using replicas of surgical tools developed in Rome and passed down through Byzantium.

However, since these tools were designed for conditions nearly 1,000 years ago, many required improvements.

Therefore, doctors in urgent battlefield situations would sterilize whatever tools were available by heating them in fire or boiling water before use.

Interestingly, sterilization and disinfection were practiced despite the lack of knowledge about bacteria. This resulted from the combination of Prince Hyang’s strict training, the experience of senior doctors who had worked under such training in the field, and the ingrained precautions recorded in Roman medical texts imported from the Western Regions.

As a side note, the dramatic difference in survival rates between those treated by Joseon surgeons familiar with sterilization and disinfection practices and those treated by surgeons in Ming or Europe led to a reverse flow of surgical techniques, with Western surgical methods returning to the West.

Of course, that was a story for the distant future. For now, mountains of data, improvements, and research tasks gathered from the battlefield were piled up.

It wasn’t just surgery that saw major developments.

The spread of infectious diseases was inevitable in battlefields transitioning from spring to summer with numerous wetlands. New treatments and medicines began to be researched to treat these epidemics. Additionally, as the importance of environment in preventing epidemic diseases was re-emphasized, the government conducted hygiene inspections of water sources, cities, and villages throughout Joseon.

In Hanseong alone, inspection standards for water and sewage systems were strengthened, and water quality management became more stringent for rivers including Cheonggyecheon and Jungnangcheon.

All of these developments were documented and transferred to the Office of Records. Consequently, the red markings on the pillars of the Office of Records grew even darker.

***

Sejong meticulously analyzed the reports analyzing this war laid before him.

“The handling of disabled soldiers seems adequate, and there appear to be no major issues with the rewards for meritorious service. But what is this participation medal?”

“It’s a medal to be attached to the uniforms of soldiers and officers who participated in this battle. It signifies that they are meritorious contributors who participated in a war that determined the nation’s fate and are veterans of a decisive battle.”

At Hyang’s answer, Sejong tilted his head slightly.

“Is this truly necessary?”

“Yes, it is. It shows that Father and the nation acknowledge those who faithfully performed their duties in their positions, even if they didn’t achieve special merit in battle. Also, having someone with experience from a major war nearby will greatly help new recruits who haven’t experienced war. Furthermore, those who wear such medals will fight more bravely in battle, if only to avoid dishonoring them.”

“Hmm…”

At Hyang’s explanation, Sejong fell into thought. However, Hyang’s expression remained resolute.

Why do you think the Demyansk Shield and Normandy Jump Badge were created in the first place?

During World War II, German soldiers who participated in the Demyansk Pocket defense were awarded the Demyansk Shield, and American paratroopers who participated in the Normandy landings were later given commemorative badges.

After careful consideration, Sejong nodded.

“I find the Crown Prince’s words reasonable. What do you ministers think?”

To Sejong’s question, the ministers answered in unison.

“We believe it is truly a beautiful intention, Your Majesty.”

“Then let us proceed with this.”

Thus, medals were awarded to soldiers who participated in this war.

It was a small metal plate modeled after the traditional square shield, the chest shield, with gold trim around the edges. Soldiers who participated in the Amnok River battle had blue paint inside the border, while those who fought in the Liaodong battle had brown. Those who participated in both battles received medals split between blue and brown.

Similar medals were given to naval forces, with green for those deployed in the Amnok River battle and yellow for those in the West Sea battle. Those who went through the West Sea battle and participated in the Jenam Fortress entry received yellow and blue medals, while those deployed in the Shanhaiguan assault received yellow and brown medals.

Those who received these medals treasured them like family heirlooms. When they went out on leave or vacation, they proudly walked the streets with these medals on their chests.

The medals had an unexpected effect: the number of soldiers causing trouble outside dramatically decreased.

“You’re not worthy of that medal!”

Those who caused trouble while wearing their medals were cursed at and ostracized by their comrades, naturally leading them to be more careful about their behavior.

As a side note, these medals also became family heirlooms and later became items that collectors worldwide desperately sought after.

***

Not everything that emerged from analyzing the war reports was positive. Some negative aspects and future concerns also surfaced.

The case of firearms that disappeared during combat was one such concern.

“If these fell into the hands of bandits or the Jurchen people, our worries would be less. We could handle it since they would have ammunition supply issues. The problem is if they reached Ming. What do you think?”

To Sejong’s words, Hyang calmly replied.

“They definitely did get some.”

It was principle for Joseon forces to carry all their weapons when retreating, even during withdrawal. They were trained to damage the firing mechanisms of heavy weapons like fire carts or scattered-shot cannons if they might be captured, and to gather and detonate items like flying heaven-shaking thunder bombs or thrown explosives according to doctrine.

However, it was almost impossible to properly follow these rules in actual combat.

Particularly during the trench warfare at the Battle of Guangning, considerable numbers of long rifles, fire carts, and scattered-shot cannons disappeared during the back-and-forth fighting over trenches.

Although they recovered much of the lost weaponry during the subsequent pursuit, the numbers still didn’t add up.

At Hyang’s answer, Sejong nodded and asked.

“Indeed? Then Ming will soon make similar weapons?”

“It won’t be easy right away.”

“Why not?”

“Because of the fulminate.”

The proper use of current Joseon military weapons absolutely required primers. And to make proper primers, mercury fulminate, named “explosive silver,” was absolutely necessary.

Hyang continued his explanation to Sejong.

“To properly and powerfully use armored explosives, explosive oil, and improved explosive oil-dynamite-fulminate is absolutely essential. And this fulminate cannot be reproduced just by looking at it.”

“So they can’t immediately copy it?”

At Sejong’s question, Hyang immediately nodded.

“Yes. In my opinion, they will first try to copy the rifling in gun barrels. Even that alone would greatly improve performance.”

All the ministers nodded along with Sejong at Hyang’s explanation. Looking at the report, Sejong asked Hyang again.

“Is that why you mentioned it would take up to ten years?”

“Yes. If they are determined, they will conduct all sorts of experiments to create something similar to fulminate. If they’re lucky, they might get results quickly; if not, it will take longer. But it shouldn’t take more than ten years regardless. They only need something with similar properties, not an exact copy.”

“Then do we have countermeasures prepared?”

“We have plans ready. First, we are preparing to develop new firearms to replace the fire carts and scattered-shot cannons, as well as new long rifles for soldiers to use.”

As soon as Hyang finished speaking, Sejong turned to Kim Jeom and Park Jong-woo.

“Deputy Prime Minister and Minister of Finance, please allocate the necessary budget. Ming will never forget this humiliation and will certainly seek revenge. And we cannot ignore Japan either. Looking at the nature of the Japanese people, they are duplicitous and unrestrained in pursuing their desires. They maintain friendly relations now because our Joseon is strong, but they will show their ferocity at the slightest opening. Therefore, we have no choice but to keep staying ahead.”

“We receive your command!”

As soon as Kim Jeom and Park Jong-woo responded, Sejong turned to Hyang.

“Crown Prince, I command you. Most of the weapons our Joseon military uses now have passed through your hands. Therefore, before you inherit my position, complete the development of weapons that will support Joseon’s military future. No, at minimum, you must create replacements for the long rifles, fire carts, and scattered-shot cannons. And for the rest, at least establish the direction for development.”

“I receive your command!”

Hyang responded loudly to Sejong’s order.

Hot damn! The wallet’s wide open! I’ll indulge in historically memorable geekery!

And everyone who heard Hyang’s response thought the same thing.

He’s excited.

He’s thrilled.

And the court historian who recorded all this added:

-… Thus when His Majesty commanded the development of weapons in preparation for future wars, the Crown Prince responded with a loud voice.

The historian says:

There is no room for dispute that the Crown Prince has great interest in weapons and has achieved great merit in developing new weapons. Since His Majesty has promised definite support, it is certain that historically memorable weapons will be born.

But to speak frankly. Weapons development is the Crown Prince’s hobby. Nothing in the world is more enjoyable than pursuing one’s hobby without financial worries. I’m envious.

***

Although the analysis and review of the battles in Liaodong were complete, the court had no time to rest.

This was because analysis and review of various policies and strict regulations implemented in the new territories followed.

While court officials and native officials from the new territories were all walking around with exhausted faces, Sejong dropped a bombshell.

The ‘greatest legal debate since the Great Reform’ was about to begin.