The Japanese Invasion of Korea 1592-93

Brace yourselves this is a long post...

Some four and a half years ago a friend was looking around for a new army to collect and asked "what about the Perry Miniatures Samurai/Korean ranges?" I was cold the idea, but the seed was planted and in 2019 when I began looking for ideas for a game at our annual Tarawera Week I warmed to it. We decided to do this as a secret game for the 2021 event - revealing the details only on the night before the game - and we began to collect the armies. I focused on the Japanese and he on the Koreans - for good reason…his wife is Korean and would have been skinned alive had he collected any Japanese units.

Having built the armies and a huge amount of terrain (the details of which will be described in future posts), the arrival of that bloody virus and its associated lockdowns together with the unavailability of our host saw the 2021, 2022, 2023 and 2024 Tarawera events cancelled. Those beautiful armies and all that terrain sat in boxes in our respective garages. Now it is time to let them see the light of day and the plan is to run the game at our regular venue, with one or two differences on 30 June.

Brief Historical Overview Supporting the Scenario

With the start of the Onin War in 1467 Japan entered what is known as the Sengoku  or 'Waring States' period that saw almost constant civil war in Japan throughout the 15th and 16th Centuries, but by 1590 the Diamyo Toyotomi Hideyoshi had succeeded in unifying Japan. Believing in a yet greater destiny he sought to expand Japanese influence in Asia by conquering the weakened Ming dynasty in China and then extending down through Vietnam, Cambodia, Burma and Siam and on to India. In May 1592, with an army of approximately 158,000 troops, he launched the first of two invasions of the Korean peninsula. By this route he sought passage into China.

The First Contingent of the invading force, led by Konishi Yukinaga, landed at Pusan on 23 May 1592. Within a day the city was taken and Konishi turned north making for Seoul. At lightening speed he moved north taking the fortress of Dong­nae on 25 May before driving  on past the mountain fortress at Yangsan and captured the castle at Miryang the following day. He then secured Cheongdo and destroyed the city of Taegu. By 3 June the he had crossed the Nakdong River, and stopped at the Sonsan mountains. There, in the strategically import­ant Choryong (Bird Nest) Pass, the Koreans made their first serious attempt to halt the invasion, but were badly defeated in the Battle of Sangju. Three days later the Koreans were decimated at the Battle of Chungju.

In desperation the Koreans sent envoys to Beijing to ask the Emperor to send an army to drive out the Japanese. The Emperor assured the Koreans that an army would be sent, but he was facing multiple revolts within the Empire that needed to be dealt with first. The Koreans would just have to wait.

Kato Kiyomasa’s Second Contingent landed in Pusan on 27 May, and Kuroda Nagamasa’s Third Contin­gent, west of Nakdong, the next day. Furious that Konishi has pressed on ahead Kato, followed by Kuroda, raced after him capturing other castles and cities along the way,  Kato caught up with Konishi at Chungju, with the Third Contingent close behind. There followed an angry exchange between Kato and Konishi with Kato claiming that Konishi had pressed far ahead of the other contingents in order to take all of the glory for himself. To soothe Kato's anger a compromise was settled on for the final advance on Seoul by splitting the forces into two separate groups to follow different routes to the Ko­rean capital. Kato was permitted to choose his route first and he chose the more direct route, but that track crossed the Han River at its widest point just south of Seoul and without boats he was unable to force a crossing. Konishi took a more easterly route that crossed the Han near its  headwaters where it posed less of a barrier and as a result he arrived at Seoul ahead of his rival on 10 June. 

Finding that the Korean King Sonjo had fled the day before Konishi occupied the undefended city. Kato arrived at the capital the next day and the Third and Fourth Contingents the day after. Meanwhile, other Contingents had landed at Pusan, while the Ninth Contingent kept in reserve on the island of Iki.
Having advanced almost half the length of the Korean peninsula, nearly 350 kilometers, in eighteen days the Japanese rested in Seoul for two weeks. When they set off again they inflicted a huge defeat on the Koreans at the Imjin River and the Koreans retreated to Pyongyang. The Japanese divided again with Konishi and Kuroda pursing the Koreans towards Pyongyang while Kato swung East and attacked Hamgyong Province.

By mid-July Konishi was opposite Pyongyang where he again defeated the Koreans, who promptly abandoned the city and retreated with the King to Uija on the Yalu River, the natural border between China and Korea. On 20 July Konishi entered Pyongyang securing over 100,000 tons of military sup­plies and grain.

While the Korean army had proven ineffective, the navy had not and had inflicted severe defeats on the Japanese, destroying more than 300 ships, effectively denying them access to the Yellow Sea. The vulnerability of the Japanese position now became apparent because without access to the Yellow Sea supplies and reinforcements had to be travel inland across mountainous terrain for nearly 550 kilometers up the centre of the peninsula. What was worse was that swath the Japanese  had cut was a narrow one and vulnerable to attack.

With nearly all of the Korean regular troops withdrawn to the north, various guerrilla groups began to form to protect the provinces from the ravages of the Japanese. As they grew larger and bolder these groups began to attack isolated garrisons and as August slipped by the fortified city of Chongju became the centre of their attention.

A location of  strategic importance on the main transportation artery running north–south up the middle of the Korean Peninsula, Chongju also served as the economic center for the entire central region and housed a large government granary.  The city had been taken on June 4 by Kuroda and after securing this prize he left behind a small unit to hold the city until reinforcements arrived.  In due course a force of 7,200 men under Hachisuka Iemasa of the fifth contingent arrived to relieve the garrison Kuroda had left and then settled down to an uneventful wait. It soon proved too uneventful for Hachisuka Iemasa who left for Seoul in late-August leaving his subordinates to deal with the ever-in­creasing guerrilla activity. 

On 6 September the guerrilla leader Cho Hon, supported by a force of monk-sol­diers, attacked the place and drove off the Japanese garrison, which retreated  to Daejon to the south. With this strate­gically placed city back in their hands, the Koreans had effectively severed the main Japanese supply line. 

When Hachisuka Iemasa heard that the place has fallen he was furious and or­dered his five subordinates to retake the it before his return or Hari Kari would be required. Since the rice harvest was well under way he gave specific orders to secure as much of the supply as possible. The  destruction of the Temple of Infinite Harmony - a source of religious inspiration  in the area - is also desirable.

It is in those last three paragraphs that I have deviated from the historical narrative and where the game begins.

In the game there are five Japanese players, two Korean guerrilla players and two umpire controlled Korean forces. 

The Japanese Players Briefing

You are  one of Hachisuka Iemasa’s clan leaders ordered to Chongju and retake the place and secure the rice harvest. No quarter is to be given. Special honours will bestowed on any leader whose clan destroys the Temple of Infinite Harmony.

There are five commands, all eight units strong, but each with a slightly different troop mix. Before the game begins you will draw straws with the other Japanese players and the longest straw had first choice of the commands, the next longest will then choose his command, and so on. 

Next you will play a short game to determine where and when you arrive on the table. It is a simple snakes and ladders game where each player begins at the START point and then moves by one of the coloured routes by rolling 1xD6 and moving the number of hexes as indicated by the die score, obeying any Miss a Turn, Go Back or Go Forward instructions. You may change the coloured track by using the grey hexes but may only travel in the direction indicated by the red arrow, the exception being the lower grey track between orange and yellow that can be traversed in either direction.

The Pre-Game Map

The Five Samurai Commands

Kuroda Nagamasa

• 1 unit Mounted Samurai
• 1 unit Foot Samurai
• 2 units Ashigaru Arquebus
• 2 units Ashigaru Yari
• 2 units Ashigaru Naganata
• 1 Ninja 

This is balanced force with a good mix of firepower and close combat troops.

Ahimazu Yoshiihisa

• 1 unit Mounted Samurai
• 2 small units Foot Samurai
• 1 unit Ashigaru Arquebus
• 1 unit Ashigaru Bow
• 1 units Ashigaru Yari,
• 2 units Ashigaru Naginata
• 1 Ninja

Again a balanced force with a slightly heavier weighting on close combat, but light on firepower.

Il Naomassa - “Lord of the Red Devils”

• 2 small units Mounted Samurai
• 2 small units Foot Samurai
• 1 unit Ashigaru Arquebus
• 2 units Ashigaru Yari
• 1 unit Ashigaru Naginata
• 1Ninja

The most aggressive of the five commands with four samurai but light on fire power.

Kato Kiyomasa

• 2 units Foot Samurai
• 1 unit Ashigaru Arquebus
• 2 units Ashigaru Bow
• 3 units Ashigaru Yari
• 1 Ninja

While it lacks cavalry it has strong contingent of close combat troops. It has reasonable firepower, albeit a heavier weight of bow armed troops

Mastuura Shigenobu

• 2 units Foot Samurai
• 3 unit Ashigaru Arquebus
• 1 unit Ashigaru Bow
• 2 units Ashigaru Yari
• 1 Ninja

The best of the five commands for firepower. It lacks cavalry but still has four units of close combat troops.

Hachisuka Iemasa

There is a chance that Iemasa will make an appearance midway through the game with this personal escort

• 1 small unit of  Foot Samurai

Unit sizes are:

• Standard cavalry unit 9 figures (3 stands)
• Standard infantry unit  18 figures (3 stands)  
• Small cavalry unit 6 figures (2 stands)
• Small infantry unit 12 figures (2 stands)
• Tiny cavalry unit 3 figures (1 stand)
• Tiny infantry unit 6 figures (1 stand)

The best of the five commands for firepower. It lacks cavalry by still has four unit units of close combat troops.

Terrain

Chongju is a fortified town that stands on the floodplain of the Geum River, a tributary of the Han, approximately mid-way between Seoul and Daegu. Surrounded by mountains in the west and east the Guem valley is a major rice growing areas and is heavily cultivated. The mountains, hills and river bottoms feature dense bamboo groves in which guerrilla groups are known to operate.

The map below is the indicative of the broader area but in no way an accurate depiction of the game table.

Victory Conditions

To win the game players needed to both compete and co-operate with their fellow clans to defeat the en­emy, capture and sack the castle. The overall winner was decided by the total number of Honour Points (represented by coins) amassed. All players commence the game with no honour points then gathered them at the following rates:

+1 each Korean regular unit destroyed by their clan

+1 for each enemy leader killed in close combat with a unit of their  clan

+2 if the guerrilla leader Cho Hon is killed in combat with a unit of their clan 

+1 if their clan is the first to enter the castle  

+1 if their clan places its banner first at the designated point

+1 if a unit in their clan destroys the Temple of Infinate Harmony

-1 for each Samurai unit of your their that rout

-2 if they assassinate another player and the Ninja can be linked to them

In the event of a draw the player who holds the most rice wagons will be ruled the winner.

There will be a prize for winning.

Information about the armies:

The Japanese Army

Samurai
Either mounted or on foot the Samurai are highly skilled and motivated. Man-to-man they are arguably the best warriors in Asia. Only a small number of Samu­rai were mounted in Korea. They hold the advantage in hand to hand combat, even better if they are led into battle by their clan leader or one of their heroes. They are variously armed with katana, yari, or naginata, but fight as mixed arm troops

• Samurai have a unique fighting factor of +2 against all .
• Can count an additional +2 factor above the normal modifier in any combat if joined by their clan leader
• Can count an additional factor of +1 or +2 above the normal modifier in any combat if joined by one of their clan heroes
• Can rally back to a “1” status if joined by their clan leader or “2” if joined by an inspirational hero

Ashigaru
 The basic foot soldier of the Japanese armies, they come in four types of units:
 
Arquebusiers - The arquebus was the key to the success of the Samurai armies in Korea. Although slow to load it had greater range and hitting power than bows. To represent the slower loading time a 'fired' marker is placed beside any unit that fires. That marker can hbe removed by the unit not firing for a turn, but if they do fire while a marker is placed the score to hit is 5+ instead of the usual 3+. If in good order and no 'fired' counter is in play, and hits from closing fire are rerolled and a 6 doubles the hit. Any troops in the open hit by arquebus fire will save on a 5+ instead of the usual 4+.

Bowmen - Outranged by the Kore­an bow and superseded by the arquebus by 1592 Korea the bow was on its way out in Japanese warfare. Japanese bows score hits at 5+

Naganata Men -  Naginata armed troops can get a +2 factor in combat

Yari men - Yari armed troops get a +2 factor in combat and an additional +1 in combat against cavalry

Ninjas - Skilled fighters Ninjas can be used to in two ways:

• As assassins to try to take out your opponent’s leader…but beware if the attempt is traced back…
• As spies to try to find any secret passages into the fortress.

Each player can have one ninja in play at any one time. The figure is placed on the table and moves at a special rate. Each time a ninja comes within 100 mm of a unit (Japanese or Korean) the unit will roll 2xD6 and 12 will mean that the Ninja may be seen. The ninja then rolls 1xD6 and a score of 4+ to avoid detection. If seen Ninjas can be shot at with a 5+ to hit and a 3+ to save.

Ninjas within 50mm of a Clan leader can attempt to assassinate him by rolling 1xD6:

• a blatant attempt will kill on 5 or 6 and wound on a 2,3,4
• a sneaky attempt will kill on a 6 and wound on a 5.

After any assassination attempt a ninja must roll 1xD6:

• If it was a blatant attempt a 3+ means that it can be traced back to the Ninja owner and the owner will lose 2 honour points 
• If it was a sneaky attempt a 5+ means that it can be traced back to the Ninja owner and the owner will lose 2 honour points

A ninja that comes within 50mm of the castle wall will draw a chit from the ninja stack and if a secret passage is found its location will be marked on the chit. He does not have to reveal the location to other players.

The Korean Army

Cavalry
The Korean cavalry were the best troops in their army. They are variously armed with swords, flails and Sam Hyul Chong - a three barreled rocket launcher. To represent their effectiveness:

• All can shoot in closing fire - charging troops will shoot a 5+ to hit, otherwise it is a 3+ to hit

Heavy Infantry
 The bulk of the Korean infantry. There are two types:
 
Heavy Armoured Spearmen
 These makes up the bulk of the Korean infantry they fight with sword, bow spear and shield

• If they use bows they will hit on a 5+
• They cannot engage in closing fire
• No other specific rule differences apply

Armoured Archers

• With better bows than the Japanese, they will hit on  a 3+
• They can engage in closing fire

Garrison Infantry
Garrison troops of the of the fortifications. They are a mixed unit with two stands of spearmen and one of archers. They can shoot as a standard unit, but will shoot at a +5 to hit. Can engage in closing fire.
 

Monks - Exceptional fighters, but only exist as small or tiny units

• +2 in combat
• Archers hit on a 3+

Guerril­las - Experts in Ambush and defense, but only exist in small or tiny units

• Capable of ambushes. They get a +5 in combat if ambushing
• In the event if a drawn combat they can break off the combat and retreat to cover and if unseen can disappear back into forests to ambush elsewhere
• They get a -1 if fighting in the open beyond the first round of an ambush

Artillery
Two types of Korean artillery exist:
 
Hwa Go - a multi-barrelled artillery piece

• Normally hit on a 3+. To represent the slower loading time a 'fired' marker is placed beside any unit that fires. That marker can be removed by the unit not firing for a turn, but if they do fire while a marker is placed the score to hit is 5+ instead of the usual 3+. All hits are rerolled and a 6 doubles the hit.

Multi Rocket Launcher - Launches a flurry of arrows fired by rockets

• Normally hit on a 3+. To represent the slower loading time a 'fired' marker is placed beside any unit that fires. That marker can be removed by the unit not firing for a turn, but if they do fire while a marker is placed the score to hit is 5+ instead of the usual 3+. All hits are rerolled and a 5 doubles and a 6 triples the hit.

Special Rules

Clan Leaders and Heroes
Each player commences the game with a clan leader and two hero figures, all are samurai, They can assist players in four possible ways.

1: They can add dice to the dice pool in a combat:

• Clan leaders add +2 to any unit fighting plus an additional +2 if the unit is samurai
• Heroes add the personal rating to any fighting unit (personal ratings are determined at the first time they are used by rolling 1xD6 - a score of 1=0, 2,3,4,5=1, 6=2).
• You cannot combine heroes and leaders to get additional dice - only one leader or hero per unit.

2: They can assist in rallying troops by contributing to their activation score
3: They can help units to recover from permanent loss of order:

• If a unit with a clan leader attached scores a “rally result” in their activation it can rally back to a “1’”status after their next activation
• If a unit with a hero attached scores a “rally result” in their activation it can rally back to a “2” status after their next activation.

4: They can make attacks as a standalone tiny unit adding all the normal combat factors (except the additional +2 for a clan leader or +0-2 for a hero joing a Samurai unit). In such attacks they cannot rout or retreat and will fight on unless the difference betweeen scores is 2 or greater in which case the leader/hero will roll 1xD6 and a score of 3+ means the leader/herso is killed, otherwise he is captured. A captured leader or hero counts as a negative honour point.

If killed heroes and leaders do not return, but their clan can fight on and amass honour points. A hero can take over from a clan leader if the latter is killed.

Ambushes

Guerrillas and Monk Soldiers can spring ambushes from any building, bamboo grove, wood or treeline that is not currently occupied.

Any units within ambush areas cannot be identified until troops come within 100mm of the area.

When an ambush is sprung, the attacking unit has a special combat factor of +5 in the first turn of combat.

There is the detail for the Japanese players. Since much of what they will encounter is unknown to them that is all I will not describe here until the day of conflict. 

And now some more pictures of toys. This time it is the Koreans.

Disclaimer: I did not purchase or paint any of those figures. My only part in the creation of the Korean force was to finish off the basing and add the standards.

The Cavalry

The Artillery

The Heavy Infantry

The Monk Soldiers

The Guerillas

The regular armoured missile troops

The Garrison Spearmen

Garrison bowmen