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Bizzare Naval Tech corner: #2 The Korean “Geobukseon” (turtle ship); what happens when a revolutionary design is wielded by a naval genius.

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#2 The Korean “Geobukseon” (turtle ship); what happens when a revolutionary design is wielded by a naval genius.

 

 

Hello and welcome to the second installment of Bizzare Naval Tech, this time with a very interesting design from Asia, the “Geobukseon” or turtle ship. In addition, we will see how it’s “inventor”, Korean Admiral Yi Sun-sin managed with the help of this ship to triumph against the Japanese, often overcoming overwhelming odds. Please forgive any mistakes in my English, not my mother tongue. :Smile_hiding:

 

Introduction

The era we will be examining this time is the late 16th century, more specifically 1592-1598, a time period during which the Japanese attempted to invade Korea twice (and China) under the leadership of Toyotomi Hideyoshi.

The Japanese way of fighting at sea was inspired by land battles, with boarding actions by samurai and widespread use of well drilled Ashigaru (common troops) armed with matchlock firearms. Some of the Japanese ships even resembled fortresses with superstructures. Most lacked cannons. Of course, such ships were mostly suitable for coastal actions.

The Japanese had some distinct advantages over the Koreans; samurai were unparalleled in hand to hand combat in boarding actions, matchlock firearms were pretty deadly. Most importantly we are talking about a Japan near the end of the Sengoku Period, with numerous troops being battle hardened and very experienced thanks to a century of almost constant war. This lead to the Japanese being dominant in land battles during both invasions of Korea.

On the other hand Korea at that time was at the forefront of naval technology in the region. They employed large numbers of cannons on their ships, with the more common “panokseon” type of ship outranging most Japanese ships.  However the Koreans found themselves early in the war being forced to scuttle a large portion of their fleet, with the Japanese warships outnumbering them.

This is when “Geobukseon” and Admiral Yi Sun-sin appear.

 

Design of “Geobukseon”:

“Geobukseon” or turtle ship was one of the newest breakthroughs in Korean naval technology. It’s creator is considered to be Admiral Yi Sun-sin, although the design already existed and he simply realized it to it’s full, at that time modern potential. So, what was a turtle ship?

Simply put, it was a type of large and relatively fast warship that was armed to the brim with cannons, was strong enough to protect it’s crew from matchlock fire and was covered at the top with spikes to make boarding nigh impossible. On the bow there was a good luck  dragon’s head. It could house a cannon, or could be used as a form of sulfur smoke projector to conceal the ship. The ship itself could turn on its radius and because of the combination of sails and oars was surprisingly quick.  As you can see, it was a vessel perfectly designed to counter the preferred Japanese naval fighting method.

A bit more detailed information from a historian describing the ship:

http://aas2.asian-studies.org/EAA/EAA-Archives/12/1/772.pdf

Quote

“His (Yi’s) ships were almost twice as long and half as wide (110 feet by 38) as their Japanese counterparts, making them move much faster through the water, while his cannon could outrange Japanese musket balls. He could thus keep Japanese ships at a distance and pound them into pieces, using perhaps as many as forty 36-pound cannons firing through hatches along its side (additional single cannon were mounted in the mouth of the good luck-at-tracting dragon’s head carved into the prow and beneath the stern transom)”.

 

 

 

  Turtle-ship-Korea.jpg.116090a2a68340b0ab3e17bccdf4e6db.jpg

A modern full sized replica of a turtle ship, this one is a museum piece. You can barely notice the spikes covering the deck.

300px-Turtle_boat.jpg.88b314f83701769751bfeacb3b118f94.jpg

A small replica of the ship in a museum

 

From Admiral Yi’s report to King Sonjo on the ship itself:

Quote

"Previously, foreseeing the Japanese invasion, I had a turtle ship made...with a dragon's head, from whose mouth we could fire cannons, and with iron spikes on its back to pierce the enemy's feet when they tried to board. Because it is in the shape of a turtle, our men can look out from inside, but the enemy cannot look in from outside. It moves so swiftly that it can plunge into the midst of even many hundreds of enemy vessel in any weather to attack them with cannonballs and fire throwers".

 

1024px-TurtleShip1795.thumb.jpg.97f90c26693742a965b1996e7aa4bc83.jpg

One of the earliest drawings depicting a turtle ship. Notice the front anchor, it was often used for ramming as well

 

Some sources consider turtle ships to have had a metal cover on the top deck, making them the first iron clad ships in history. This is disputed however since iron at the time was in short supply and the thick wood was already proof to most forms of damage.

While not many of these ships were made (at the height of the war about 6 to 8 are considered to have been in use), they were used to tip the scale in the many naval battles during the war. They were used as breakthrough vessels, able to enter deep within enemy formations and use the cannon to wreak havoc, often focusing on sinking the enemy flagships.

 

Usage of the turtle ship and disadvantages

For this section I chose two of the better known battles in which turtle ships were used and were important in securing victories.

The first one is the battle of Sacheon (1592). Always under the command of Admiral Yi, the Korean nay encountered 12 large battleships in the harbor of Sacheon. By feigning retreat the Koreans managed to lure the Japanese ships. Then, the Korean fleet turned, and with a turtle ship at the front rushed to fight the Japanese. Due to the inability of the Japanese to cause any damage they lost all their battleships, while the Koreans only had 5 wounded (including Admiral Yi).

At the battle of Tanghanp’o, the same tactic of feigning retreat was used, followed by an ambush at open waters. Again the turtle ship played an important role in the win, rushing to the enemy flagship, ramming it and devastating it with cannon fire.

From Admiral Yi’s report to King Sonjo on the battle:

Quote

“Then our ships suddenly enveloped the enemy craft from the four directions, attacking them from both flanks at full speed. The turtle with the Flying Squadron Chief on board rammed the enemy's pavilion vessel once again, while wrecking it with cannon fire and our other ships hit its brocade curtains and sails with fire arrows. Furious flames burst out and the enemy commander fell dead from an arrow hit".

 

 

1606486.jpg.6fbd051552d6d1d0d15f1fb297917f4e.jpg

A turtle ship in it’s favorite place, in the middle of everything and rushing an Atakebune (particularly large Japanese warships that served as flagships)

 

While impressive, turtle ships weren’t invincible machines of naval war. They were more suited to coastal actions and not open waters. In addition they were very expensive to produce and required many resources. Last, their performance relied on good leadership and tactics; when Admiral Yi lost command of the fleet for a time, his successor, eager to prove his worth managed to lose almost his entire fleet pretty quickly.

 

Admiral Yi Sun-sin

While the focus of these articles is on naval designs, there has to be some further mention on Admiral Yi Sun-sin, an admiral that had no naval training, was never defeated, never lost a single ship and lost his life while fighting for his country in 1598. He was considered by historians and military leaders as one of the greatest naval minds in history.

In the words of Admiral George Alexander Ballard:

Quote

 

“It is always difficult for Englishmen to admit that Nelson ever had an equal in his profession, but if any man is entitled to be so regarded, it should be this great naval commander of Asiatic race who never knew defeat and died in the presence of the enemy; of whose movements a track-chart might be compiled from the wrecks of hundreds of Japanese ships lying with their valiant crews at the bottom of the sea, off the coasts of the Korean peninsula... and it seems, in truth, no exaggeration to assert that from first to last he never made a mistake, for his work was so complete under each variety of circumstances as to defy criticism... His whole career might be summarized by saying that, although he had no lessons from past history to serve as a guide, he waged war on the sea as it should be waged if it is to produce definite results, and ended by making the supreme sacrifice of a defender of his country. (The Influence of the Sea on The Political History of Japan, pp. 66–67.)”

 

 

admiralyi.jpg.0449e83dfc96dc764ebe45dfde6d5d44.jpg

Statue of the man himself in Seoul

 

Thanks to his ships and tactics he managed to always emerge as the victor, utilizing his ships in the best possible way and using every possible factor to secure advantages in battle.He is famous for the feigning retreat tactics as we already saw, as well as the “crane maneuver” that gave him victory in important battles such as the one on Hansando

 

f0095962_4b14b07add971.jpg.de7dfe1851cd5b4b4ca9fc07738f9d26.jpg

A depiction of the crane formation during the battle of Hansado; blue depicts the Koreans, red the Japanese; this maneuver enabled the numerically inferior Korean navy to surround the Japanese and ensure a decisive victory.

 

Perhaps his greatest victory however was in the battle of Myeongnyang in 1597 during the second invasion of Korea. After most of his fleet was lost thanks to the incompetence of his predecessor he decided to make a final stand at Myeongryang Strait. The reason for this choice was the narrowness of the Strait as well as the currents that flowed in different directions every three hours. He faced 130 Japanese warships with just 13. At the start of the battle, due to his own fleet being scared and shaken, he fought alone in his flagship against the whole Japanese fleet.

In his words from his diary:

Quote

"My flagship was alone facing the enemy formation. Only my ship fired cannons and arrows. None of the other ships advanced, so I could not assure our outcome. All other officers were seeking to run, as they knew this battle was against a massive force. Ship commanded by Kim Eok-chu, the Officer of Jeolla Right province, was at 1 majang (approximately 2–3 km) away."

 

Managing to rally his fleet and using the current that had shifted by that time, he delivered a crushing blow to the Japanese fleet, destroying 30 ships and killing half of the enemy forces to no ship losses on his side.

Conclusion:

With the successful use of turtle ships and the leadership of Admiral Yi, the Japanese land forces quickly found themselves with their supply lines in peril. They were unable to seize any advantages their superiority on land provided them thanks to the Korean dominance at sea. Eventually their plan of conquering Korea failed.

I specifically chose the turtle ship as a prime example of how in the end technological advancements often require the human factor to really shine.  In combination with the genius of Admiral Yi they were deadly weapons that succeeded in defending their country.

Thanks for reading and I hope you enjoy this subject as much as I did writing and researching about it. As usual I would welcome any comments, be they negative and giving me some constructive criticism, or positive for my work.

Thanks again for reading!

 

Sources:

https://en.wikipedia.org/wiki/Turtle_ship

http://aas2.asian-studies.org/EAA/EAA-Archives/12/1/772.pdf

https://deadliestblogpage.wordpress.com/2017/07/23/great-warships-of-history-korean-turtle-ship/

https://en.wikipedia.org/wiki/Japanese_invasions_of_Korea_(1592%E2%80%931598)

http://www.newworldencyclopedia.org/entry/Turtle_ship

http://www.antiquealive.com/Blogs/Geobukseon_Turtle_Ship.html

https://en.wikipedia.org/wiki/Battle_of_Myeongnyang

Previous article in case anyone is interested

 

Edited by warheart1992
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130 vs 13 and it wasn't a fair fight.

From the Korean movie The Admiral Roaring Currents.

 

 

 

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2 hours ago, warheart1992 said:

While impressive, turtle ships weren’t invincible machines of naval war. They were more suited to coastal actions and not open waters. In addition they were very expensive to produce and required many resources. Last, their performance relied on good leadership and tactics; when Admiral Yi lost command of the fleet for a time, his successor, eager to prove his worth managed to lose almost his entire fleet pretty quickly.

To be fair, the Japanese ships, especially the Japanese Floating Castle Nihon Maru were more suited to coastal actions as well.  Also expensive to produce and required many resources.

The big difference was that the major Japanese Bunes lacked cannons so that were always at a disadvantage against Korean cannon-armed ships.  I can't exactly say the Turtle Ship's Ironclad armor was all that decisive.  Just equipping your ships with cannons in this time period would be all the advantage you'd need to defeat a larger force laking cannons.

Edited by Royeaux

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7 minutes ago, Royeaux said:

To be fair, the Japanese ships, especially the Japanese Floating Castle Nihon Maru were more suited to coastal actions as well.  Also expensive to produce and required many resources.

The big difference was that the major Japanese Bunes lacked canons so that were always at a disadvantage against Korean cannon-armed ships.  I can't exactly say the Turtle Ship's Ironclad armor was all that decisive.  Just equipping your ships with cannons in this time period would be all the advantage you'd need to defeat a larger force laking cannons.

Of course, just needed to be said. As for the ironclad part, most think it never existed. The thick wood protected against the firearms the japanese tended to use so it would be overkill. 

There is an entry in Admiral Yi's diary where he feels the need to mention he spent 50 pounds of iron on the ship. That was nowhere near close to armouring the ship, so it was most likely spent on making the spikes. Besides, afaik for most of the first invasion the area where he operated was cut of from the rest, making procuring resources pretty difficult. 

Last, the main ship of the Koreans, the panokseon also carried large amounts of cannon. It was the ability of the turtle ship to move surprisingly fast and be nigh immune to firearms and  boarding that made it such a threat, at least iny opinion.:Smile_honoring:

Edited by warheart1992

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This war in general had far reaching effects.

 

Even though it won, Korea was ruined.

For Japan, a lot of Hideyoshi's supporters were the ones sending the forces to fight in Korea and they bore the losses.  When Hideyoshi died, his faction lacked his leadership and lost military strength from Korea and would lose when Tokugawa Ieyasu finally made his bid for power.  He succeeded and established the Tokugawa Shogunate that would last until the 1860s.

 

This war was also the first time that Japan would really push out for foreign conquests.  Usually they were insular or warring with each other too much to do such a thing.  It would also not be the only time Japan had aims for Korea and even China.

 

The conflict also, at least to me, stresses Korea's precarious location: in the middle of two major powers, China and Japan.  It makes me think of Poland who's right in between Germany and Russia.

 

Another interesting thing was that due to Japan's isolation and civil wars, they had not been fighting outsiders that much, other than the Mongol Invasions hundreds of years prior.  They had been fighting the Sengoku Jidai among themselves, but with the Korean campaigns, fighting vastly different forces not like them with different fighting styles and weapons.  It was fascinating how they did pretty well on land, but at sea they were being smashed.

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8 hours ago, Royeaux said:

To be fair, the Japanese ships, especially the Japanese Floating Castle Nihon Maru were more suited to coastal actions as well.  Also expensive to produce and required many resources.

The big difference was that the major Japanese Bunes lacked cannons so that were always at a disadvantage against Korean cannon-armed ships.  I can't exactly say the Turtle Ship's Ironclad armor was all that decisive.  Just equipping your ships with cannons in this time period would be all the advantage you'd need to defeat a larger force laking cannons.

 

The Portuguese provided cannons and muskets to the Japanese, although at some earlier point, the Japanese were making cannons based on Chinese ones that were brought in around the time and after of the attempted Mongol invasion.

 

However, both Japanese and Portuguese cannons and firearms  were no match to the cannons and firearms that were brought in by the Ming and served to recreate the Korean arms industry.  It would be another century or two before European firearms and cannons would surpass those used by the Chinese and the Koreans.    Initially the Koreans had inferior firearms to the Japanese but had superior bowmen and that had an effect on land battles.  Then the Ming came and brought their arms and tech with them.  

 

Most of the Japanese ships would be armed by musketeers, arrows and catapults.

Edited by Eisennagel

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24 minutes ago, Eisennagel said:

 

The Portuguese provided cannons and muskets to the Japanese, although at some earlier point, the Japanese were making cannons based on Chinese ones that were brought in around the time and after of the attempted Mongol invasion.

 

However, both Japanese and Portuguese cannons and firearms  were no match to the cannons and firearms of the Koreans which were either made by them or supplied from their Ming allies.  It would be another century or two before European firearms and cannons would surpass those used by the Chinese and the Koreans.  

By the time of Commodore Perry's arrival and the Boshin War, Japan was manufacturing wooden cannon to deal with situation.  I suspect Japan didn't have the domestic iron ore production to really compete with Korea in cannons.  During the interwar period of the World Wars, Japan was getting its "domestic" iron ore from Hokkaidō and Korea, areas not properly under control during the Korean invasions. 

As wikipedia has to say "Even though China was the main source of new military technologies in Asia, Korea was a manufacturing base for both cannon and shipbuilding during this era.  Japan, on the other hand, had been in a state of civil war for over a century, which had the result of turning Japan into a very proficient warlike society. When traders from the Portuguese Empire arrived in Japan and introduced arquebuses and muskets, the Japanese warlords were quick to adapt to this disruptive innovation, producing en masse the Tanegashima matchlock. In the ongoing civil strife, the Japanese refined the drills and tactics to make best use of the new weapon, thus giving them a great advantage over the Korean armies.

As virtually all Japanese ships in the first phase of the war lacked cannon artillery, Korean ships outranged and bombarded Japanese ships with impunity outside the range of the Japanese muskets, arrows, and catapults. When the Japanese attempted to outfit cannon to their ships, their lightweight ship design prohibited using more than a few per vessel, and vessels usually lacked the firepower or range of their Korean counterparts. In order to bolster their fleet, the Japanese considered employing two Portuguese galleons in the invasion." - https://en.wikipedia.org/wiki/Japanese_invasions_of_Korea_(1592–1598)

Sendai1868Cannons.JPG

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Tanegashima matchlocks.

 

iFKy875.jpg

 

aThsYwc.jpg

 

wPd4qyo.jpg

 

Korean matchlocks

 

V4wE9fr.jpg

 

i2XdkH7.jpg

 

Ming Dynasty matchlocks, guns and cannons.

 

DCKc79j.jpg

 

YwiERuT.jpg

 

Not sure how these babies work but I believe its like an early shotgun.

 

Z5d4q5P.jpg

 

 

NsOKakS.jpg

 

eM20Vc4.jpg

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8 minutes ago, Eisennagel said:

 

aThsYwc.jpg

 

Ah yes, the Japanese Bo-hiya, believed to have been used in the Korean invasion.  A hand held cannon that fired rockets or sometimes fire arrows.  Standard weapon in sieges or naval battles.  "Awesomest" weapon in Shogun 2 Total War.

 rocketbohiya1.jpg

 

6a555ef2755c57820d0e840c31647655.jpg

 

FoCtRtp.jpg

 

Edited by Royeaux

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1 hour ago, Royeaux said:

Ah yes, the Japanese Bo-hiya, believed to have been used in the Korean invasion.  A hand held cannon that fired rockets or sometimes fire arrows.  Standard weapon in sieges or naval battles.  "Awesomest" weapon in Shogun 2 Total War.

075.jpg

Commit sudoku!

Edited by HazeGrayUnderway

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4 hours ago, Eisennagel said:

Not sure how these babies work but I believe its like an early shotgun.

 

Z5d4q5P.jpg

 

 

NsOKakS.jpg

 

eM20Vc4.jpg

Ah, that would be the "three eyed gun", a form of hand cannon

https://en.wikipedia.org/wiki/San_yan_chong

Something interesting,

Quote

.....to a specialized short curved stock with a raised sight that enabled the gunner to fire it while kneeling- these would be called "Divine Machines."

They really liked to give their weapons fancy names :Smile_hiding:.

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Something about the Imjin Wars is that the Portuguese were bent on converting the Japanese to Christianity, and by helping the Japanese conquer Korea, they can convert Korea too, and eventually China.  The Japanese soldiers even had red crosses like crusaders.

 

a32SRQQ.jpg

 

The Korean armies were unprepared for the Japanese onslaught, and retreated after a series of defeats.  Local guerrilla armies, and among them, an army of 5,000 warrior monks, called the Righteous Army, rose to the task of defending their homeland, successfully waging a guerrilla war.  

 

tWfF7GS.jpg

 

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