Military weapons and equipment have greatly changed over the years. In 15th-century Korea, military personnel preferred a multiple rocket launcher and organ gun, known as the hwacha (or hwach’a). The rocket launcher could fire one or two hundred rocket-powered arrows, while the organ gun could fire several dozen iron-headed arrows out of gun barrels.

If you saw the hwacha in your area, it was time to run. The weapon was designed to cause damage, and you didn’t want to be located anywhere near its target. Used in the defense of the Korean Peninsula against the Japanese, the hwacha was primarily helpful towards the end of the 15th century. Many East Asian historians believe the technological weapon was a crucial aiding device during the war.

What was involved in the weapon? How was it used? You can see hwachas today in Korean museums and national parks, but you might want to learn something about their use before you make your visit.

Birth of the hwacha

Historians believe the hwacha was invented about 200 years prior to when it was first implemented in Korea during the 15th century. It’s unclear the exact day when the weapon was first invented, but the hwacha was likely developed around the same time when gunpowder was first manufactured in Korea, approximately by the 14th century.

People can credit Choe Museon for first developing a version of gunpowder. He (along with his son, Haesan Museon) advanced the production of gunpowder, and other people would do their best to replicate their efforts.

Shinkigeon-Style Hwacha
Shinkigeon-Style Hwacha / Wikimedia Commons / CC-BY-2.0

It’s believed the hwacha was originally used as a defensive weapon. By the middle of the 15th century, during the Joseon Dynasty, the weapon was manufactured in bulk by King Munjong so Korea could protect its border defenses against the opposing Japanese military. King Munjong ordered that the weapon be advanced to fire 200 projectiles at once. He also wanted the ammunition to be improved. Whatever he wanted, it was delivered.

The hwacha greatly changed the way military fighters and warriors operated their battles. It was one of the first rocket launchers, consisting of a two-wheeled cart that was mounted on a board with several holes carved into the board. The holes were filled with singijeon — machine arrows about 1.1 meters in length that were propelled by a paper tube filled with gunpowder and attached to the shaft of each arrow.

The singijeon was the earliest form of a rocket. When launched, they could travel up to 2,000 meters, which is over a mile! This was just the 15th century! It might be hard to believe there was a weapon of this kind in the 15th century, but the Koreans were very skilled. You wouldn’t want to underestimate their talents. They accomplished greatness, even if most of us have never heard of the hwacha.

But you probably have seen a more modern device that resembles the ancient war weapon.

What did the hwacha look like?

If you have seen a handcart, then you can picture the hwacha. The weapon’s structure, made of pinewood, was similar to a handcart with a wooden launchpad on the top.

The backside of the weapon had two parallel arms, which allowed the operator to push and pull the device wherever it needed to go. It also featured a vertical strip designed for in-line attacks, or it could be positioned for standing ground-sentry locations. The wheels were typically fastened by wood pivots and iron axles, and they closely resembled modern-day versions of wagon wheels.

While many hwachas were made of pinewood, several were constructed of oak. The weapon’s ropes were made of hemp, a strain of the Cannabis sativa plant.

The construction of these specialized weapons required delicate work. Because of this, the Korean army chose skilled engineers and blacksmiths to make repairs and build hwachas.

If the weapons ever suffered from any damage from poor road conditions, bad weather, or battles, the engineers knew exactly what to do to make sure they were repaired and back to their original state.

Shinkigeon-Style Hwacha (side view)
Shinkigeon-Style Hwacha (side view) / Wikimedia Commons / CC-BY-2.0

The engineers designed the hwachas to be different than any other weapons you might have seen, especially the cannons and mortars used in Western warfare during the Middle Ages and the 16th century. These weapons needed heavy iron balls, but not hwachas. Engineers designed the singijeon-class projectiles (small arrows) specifically for the hwachas, and their thin, light design made the hwachas effective, easily maneuverable weapons.

However wonderful this design might seem, engineers still faced several challenges with the weapon. The trajectory was fairly flat, and operators had to increase the elevation while firing the weapon to maximize its range. Harsh weather conditions, including wind, humidity, and rain, limited the weapon’s striking distance to about 100 meters away.

By 1592, Korea felt intensely threatened by the Japanese. The opposing Japanese forces invaded the country, launched by Japan’s great warrior Toyotomi Hideyoshi. He wanted to conquer the Korean Peninsula on his way to invading China.

At this point, Korea felt mostly defenseless against these harsh attacks during what we know today as the Imjin Wars, lasting from 1592 to 1598. Japan occupied the Korean Peninsula and captured several cities and fortresses. It seemed there was nothing Korea could do to stand a chance against the mighty Japanese forces.

However, that’s when the military decided hwachas would be their best tool to defend their country against the invasions. Hwachas were placed in fortresses and citadels, and military leaders recognized the weapon as a national defense form against the Japanese raiders. The weapon was incredibly valuable and powerful in battles, including in the famous Battle of Haengju.

Korea’s greatest victory

Japan dominated the Imjin Wars, capturing the Korean Peninsula. However, one of Korea’s greatest victories during the war was the Battle of Haengju on February 12, 1593.

Historians have reported that the battle involved 3,000 Korean soldiers, who defended a hilltop fortress against 30,000 Japanese soldiers. Looking at these numbers, it seems the Koreans would have been unable to defeat the Japanese. But despite these odds, the Koreans were victorious and delivered a heavy blow to the Japanese morale—thanks to the usage of hwachas.

The weapon was incredibly valuable and powerful in battles, including in the famous Battle of Haengju.

Korean soldiers used 40 hwachas mounted on the outer walls of their fortress. The Japanese tried to assault the fortress nine times, but they were unable to defeat the Koreans and their hwachas. This was a victory for the Koreans, but the country wouldn’t use the hwacha forever.

Retirement of the hwacha

There was no doubt that the hwacha was an important weapon of war for the Koreans. It helped protect the country and was used offensively in sea-to-land attacks and in naval warfare during major battles of the Imjin Wars. But the weapon couldn’t be used forever.

The device eventually became obsolete due to the use of other war machines. However, the hwacha is still regarded as one of the most important military weapons in Korean history. It is featured in popular culture, mostly because it helped Korea during the Battle of Haengju.

The hwacha has sometimes been assembled and tested in modern times, including in a 2008 episode of the popular science entertainment program, MythBusters. The “Myth Busters” (Adam Savage and Jamie Hyneman) tested the rocket launcher in three parts. This confirmed the supposed myth that the hwacha actually could launch and fire 200 arrows at once.

It might not seem possible that a device from the 15th century could operate like that, but just because it was created in ancient times doesn’t mean the Koreans were incapable of accomplishing greatness.

Maybe you have never heard of the hwacha before. That’s okay.

There are many other military war weapons that are unheard of in popular culture. They look like they were props on Game of Thrones, but trust us: they were real, and they helped soldiers combat in some of their more crucial battles.

For example, ancient China used flamethrowers, or fire lances, during the 10th century. The spears were attached to bamboo tubes that could shoot a burst of flame a few feet away. Some were adjusted to shoot lead pellets, while others could release a burst of poisonous gas and arrows.

The ancient Greek and Roman empires preferred a giant crossbow device, known as a bow Arcuballista. The arms of the bow didn’t bend like a normal crossbow. Instead, they were solid wood beams mounted between twisted skeins of rope. When a soldier turned a lever, the ends of the arms rotated towards the back of the device, twisting the ropes to create enough force to cause severe damage.

The Chinese perfected this device during the Tang dynasty, adding three bows. This increased the power, making the ballista fire an iron bolt up to 1,100 meters away, over three-fourths of a mile!

Military weapons have evolved throughout time. It’s important for war historians to study these ancient devices in order to know what worked in the past. Who knows? Perhaps the hwacha could still be influential in today’s military operations.

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