The Joseon Army (Korean: 조선군대; Hanja: 朝鮮軍隊) was the army of the Korean dynasty of Joseon (1392–1897). The army defended the northern borders but seldom defended the southern regions. The army was best known for fending off the Jurchen raids and conquering the Korean Peninsula. However, Joseon's neo-Confucianism disavowed military development, causing them to be vulnerable to Japanese and Manchu invasions. Despite this, Joseon kept strengthening the army until the 19th century, when western powers and the Japanese forced them to open doors and modernize the army.
History
=== Early period === The armed forces of the former Goryeo kingdom were Joseon's armed forces during the reign of King Taejo. However, the officials of the Joseon court commanded private armies from the previous kingdom. Yi Bang-won and his officers staged a coup against Taejo and his brother Jeongjong of Joseon, inciting the first and second strife of the princes. He advised Jeongjong to ban the ownership of private armies and become king in favor of having a central army. When Sejong ascended the throne, he created various military regulations to strengthen the safety of his kingdom, supported the advancement of Korean military technology, including the development of the cannon, mortars, fire arrows and the use of gunpowder.
==== Joseon–Jurchen border conflicts ==== Like Goryeo, Joseon made the Jurchens in the area around Hamhung on the northeastern Korean peninsula submit as vassals. The Joseon Koreans tried to deal with the military threat posed by the Jurchens by using both forceful means and incentives and by launching military attacks. At the same time, they tried to appease them with titles and degrees, traded with them and sought to acculturate them by having Korean women marry Jurchens and integrating them into Korean culture. Despite these measures, fighting continued between the Jurchen and the Koreans. The Ming Yongle Emperor was determined to wrest the Jurchens out of Korean influence and have China dominate them instead. Korea tried to persuade Jurchen leader Mentemu (Möngke Temür) to reject the Ming overtures, but were unsuccessful since Möngke Temür folded and submitted to the Ming. In 1433, Sejong sent Kim Chongsŏ, a prominent general, north to destroy the Jurchens. Kim's military campaign engaged the Jurchen clans such as the Odoli, Maolian and Udige capturing several castles, taking control of Hamgyong and continued pushing north expanding Korean territory to the Songhua River. He then established 4 counties, 6 garrisons, and several border forts in the region to safeguard the people from the Jurchens shaping the modern borders of Korea around 1450.
==== Oei Invasion ==== In 1419, King Sejong sent Yi Chongmu to raid the Japanese on Tsushima Island in the Oei Invasion as a response to Japanese Wokou raids on Korean coastal cities. Yi took 227 Korean ships and approximately 17,000 soldiers, landed, attacked, and plundered Japanese pirate settlements on Tsushima Island. The So clan, the ruling family of Tsushima, requested negotiations. In the diplomatic exchanges that followed, Korea permitted the So clan to continue trade with Korean coastal harbors under the condition that the clan suppresses the activities of Japanese pirates.
Yi Si-ae's Rebellion
When King Sejo came to power he strengthened the monarchy established by King Taejong by weakening the power of the State Council and bringing staff directly under the king's control. He also strengthened the administrative system to enable the government to determine exact population numbers and to mobilize troops effectively but caused Yi Si-ae's Rebellion. Yi Si-ae led the Iksok Force and the rebel army killing officials from the central government for not appointing northern officials to govern the northern provinces until they were defeated soon after the Battle of Manryeong.
Japanese Invasions of Korea
By the 16th century, the military became weak by the disavowment from Confucian scholars. During the Imjin War, Joseon mobilized few military units within a standing army. Its defense depended heavily on the mobilization of the citizen soldiers in case of emergency. When Japan invaded Korea, Joseon deployed a total of 84,500 regular troops. During the first invasion, the Joseon army was no match for their sheer numbers armed with arquebuses and a combination of arms, and the Japanese pushed them north to Pyongyang. When the navy, and the Righteous Army cut off supply lines, this gave the regular army a chance to force the Japanese back to Pusan through many strategic battles. During the 1595–1596 Truce, Seonjo realized how important it was and tried to reform it with the help of Ming generals and established army training centers. Yu Sŏngnyong, the Chief State Councillor, spoke out about the Korean disadvantages. He examined why the Japanese had quickly overrun them and pointed out the flaws of their defense systems. Yu also pointed out how efficient the Japanese army was since it took them only one month to get Hanseong and how well organized they were. He noted how the Japanese moved their units in complex maneuvers, often weakening their enemy with arquebuses, then attacking with melee weapons. These reforms helped Joseon Army repel the second invasion of the Japanese army and win the war.
Yi Gwal's Rebellion
After the Injo Coup, the dissatisfied Yi Kwal who helped Injo ascend to the throne incited a rebellion against him for trying to arrest his son, Yi Chŏn. He led 10,000 of his soldiers to occupy Hanseong and replace him with Heungangun, his royal relative as king. But the Joseon army led by General Chang Man retook the capital and crushed the rebellion. Yi Kwal's Rebellion weakened the military, making them vulnerable to Later Jin's attack.
=== Manchu-Joseon conflicts === Conservative Westerners took hard-line policy toward the Jurchen-led Later Jin dynasty, keeping their alliance with the Ming dynasty. The Later Jin, who had remained primarily friendly to Joseon, began to regard Joseon as an enemy. Han Yun, who participated in the rebellion of Yi Kwal, fled to Manchuria and urged the Later Jin ruler Nurhaci to attack Joseon; thus, the friendly relationship between the Later Jin and Joseon ended.
Battle of Sarhū
In 1619, the Joseon Expeditionary Force led Commander Gang Hong-rip to engage Later Jin with the Ming Army at the Battle of Sarhū. But the allied forces lost two-thirds of the Joseon Expeditionary Force. The Jurchen released the captives and allowed them to return to their homeland. Gang Hong-rip, however, was kept for his proficiency in the Jurchen language. Later on, General Gang would be led to believe that his family had died in the political turmoil during a coup in his native kingdom of Joseon. To exact his revenge on the Joseon court, he urged Jin to invade Joseon, which led to the First Manchu invasion of Korea in 1627. Only during the peace negotiations did he find out that he had been misled. The Joseon musketeers being overwhelmed by the Manchu cavalry prompted a revision of military tactics in Korea. In previous decades, the Imjin War was seen as a demonstration of the dominance of the firearm, and Joseon adjusted military forces accordingly. Both sides of the war lacked effective shock cavalry to take advantage of the vulnerabilities of unsupported musketeers. After the defeat at Sarhū, the Joseon forces revised their doctrine to have spearmen supporting the musketeers.
Later Jin invasion of Joseon
In 1627, 30,000 Manchu cavalries under General Amin and former Korean General Gang Hong-rip invaded Joseon, calling for the restoration of Gwanghaegun and execution of Westerners leaders, including Kim Chajŏm. General Chang Man again fought against Later Jin but could not repel the invasion. Once again, Injo fled to Ganghwa Island. Meanwhile, Jin had no reason to attack Joseon and decided to go back to prepare for war against the Ming, and peace soon settled. The Later Jin and Joseon dynasties were declared brother nations, and Later Jin withdrew from the Korean peninsula. However, most Westerners kept their hard-line policy despite the war. Nurhaci, who had generally good opinions toward Korea, did not invade Korea again; however, when Nurhaci died and Hong Taiji succeeded him as ruler, Jin again began to seek a chance for another war. King Injo provided refuge to Ming general Mao Wenlong and with his unit after they fled from Later Jin and came to Korea; this action caused Later Jin to invade Korea again.
Qing invasion of Joseon
In 1636, Hong Taiji officially renamed his dynasty the Qing dynasty and invaded Joseon personally. The Qing forces purposely avoided battle with General Im Gyeong Eop, a prominent Joseon army commander who was guarding the Uiju Fortress at the time. A Qing army of 128,000 men marched directly into Hanseong before Injo could escape to Ganghwa Island, driving Injo to Namhan Mountain Fortress instead. They ran out of food and supplies after the Manchu cut all supply lines during the siege. Injo finally surrendered to the Qing dynasty ceremoniously, bowing to the Hong Taiji nine times as Hong Taiji's servant and agreeing to the Treaty of Samjeondo, which required Injo to send his first son and second son to China as captives. Joseon then became a tributary state to the Qing dynasty, and the Qing went on to conquer the Central Plain in 1644. Though they lost the wars, their performance left a strong impression on the Manchus. The first emperor of the newly declared Qing dynasty later wrote: "The Koreans are incapable on horseback but do not transgress the principles of the military arts. They excel at infantry fighting."
Military expansion
Hyojong rose the throne after Injo and Sohyeon's death, he began to reform and expand the military of Korea. First, he removed Kim Chajŏm, who had corrupted politics and had greater power than the king himself. Then, he called Song Si-yeol and Kim Sang-heon to his court, who supported the war against the Qing Dynasty. His military expansion was massive, and he also built several border fortresses along Yalu River where Joseon and Qing shared a border. When a band of Dutch sailors, including Hendrick Hamel, drifted on Jeju Island, Hyojong ordered them to build muskets for the army, making it the first time to use firearms since the Imjin War. Hyojong could not implement his plan when his son Hyeonjong stopped him since Joseon had become a tributary state of the Qing Dynasty. The Qing dynasty continued to thrive, expanding quickly into the west after successfully conquering the Ming in 1644. Since the Manchus assimilated the massive Chinese army into their own, they became too mighty to resist. Although reformed and expanded, the Joseon military was no match against the combined Manchu and Chinese forces. Also, the Qing dynasty began to treat Joseon as its friend and closest ally. After Hyojong died, Hyeonjong rose to the throne and continued his father's military expansion and reconstruction of the nation, devastated by the Seven-Year War and two Manchu invasions.
=== Northern campaigns === The Naseon Jeongbeol, or "Suppression of the Russians" or the Northern campaign began when the expanded Joseon military was first put into action in 1654 when the Qing Dynasty called for help to fight against invading Russians. 150 Joseon musketeers, along with 3,000 Manchus, met the Russian army at the Battle of Hutong (호통; 好通), present-day Yilan, which the Qing–Joseon allied forces won. In 1658, Hyojong sent troops again to help the Qing dynasty against Russia. He dispatched 260 Joseon musketeers and cannoneers led by Shin Ryu to join the forces of Ninguta's Military Governor Sarhuda. The joint force sailed down the Hurka and Sungari Rivers and met the Russian troops under the command of an Amur Cossack, Onufrij Stepanov near the fall of the Sungari River into the Amur, killing 270 Russians and driving them out of Manchu territory. The battles against Russia proved that Hyojong's reform had stabilized the Joseon army, although they never put them into action again. Despite the campaigns, Russia and Joseon remained on good terms.
Yi In-jwa's Rebellion
Yi In-jwa attempted a coup d'état in March 1728 by a coalition of the radical faction of the Namin and the excluded Soron faction. After the death of King Gyeongjong and the ascension of King Yeongjo to the throne, the position of the Noron faction was restored, and Soron, who had instigated the rebellion under the pretext of protecting King Gyeongjong, was punished and excluded from power. Shortly after ascending to the throne, Yeongjo pursued a policy of equal recruitment, believing that factional strife was detrimental to the country's development. In response, the radical faction of the Soron group justified their rebellion by raising suspicions about the circumstances of King Gyeongjong's death and claiming that King Yeongjo was not the legitimate heir of King Sukjong, thereby securing their power. The rebellion began on 15 March when Yi In-jwa captured Cheongju Castle. The rebel forces, marching toward Hanyang (present-day Seoul), were defeated by the royal army, and the support from the Yeongnam and Honam regions was also suppressed by local forces, leading to the suppression of the rebellion.
Hong Kyŏngnae's Rebellion
By the 19th century, royal relatives controlled the royal court through weak kings causing the military to weaken further. Hong Kyŏngnae led an insurrection of former Yangban and impoverished farmers who were unhappy with their treatment by the central government and oppressive taxation. At its height, the rebellion controlled most of the area north of the Cheongcheon River, including the fortified town of Jeongju, to withstand invasions from Manchuria (part of the Qing Empire). Whenever the rebels took over a district, they opened the government granaries and distributed the grain to the people. However, the insurgents suffered disastrous defeats in the battles of Pine Grove and Four Pine Field and forced the rebels to withdraw to Jeongju, which came under a two months-long siege by government forces. The rebellion was put down a few months later, on 29 May, when the government forces breached the town wall with a gunpowder charge exploded under the wall through mining. Thousands of people caught up in the uprising, including boys older than 10, were executed. All women and boys under 10 were enslaved. Hong Kyŏngnae died in the fighting. Other rebel leaders were also killed in battle or executed.
Foreign incursions and reorganization
Joseon's isolation policies allowed the military to fire on foreign ships. When the USS General Sherman arrived at Ganghwa Island, they requested the government to open for trade, but the army sank their ship and killed their crew. In 1866, the French launched a putative expedition on Ganghwa Island to demand the government release the catholic priests, but were repulsed by the Tiger Hunters. They spearheaded the defense of Ganghwa with the army. The French left during the winter when they received news that the priests had escaped. In 1871, the Americans too launched a putative expedition to demand the government open for trade and apologize for the General Sherman Incident. The Tiger Hunters again spearheaded the defense, but the army and their coastal fortresses did not match their superior firepower. 20 Koreans were captured as bargaining chips for the Americans but released the prisoners before they left after a diplomatic failure. These small victories and foreign diplomatic defeats made the Joseon Army blind to its inferiority to modern armies. Japan plundered and pillaged Ganghwa Island for firing on their gunboat Un'yō, finally forcing them to open doors to the world and modernize the army which will eventually lead to the development of the armed forces of the Korean Empire.
== Organization == In early Joseon, the military system consisted of the Five Guards (Owi, 五衛) and the Royal Guard (Geumgun, 禁軍) at the central level, while the Jingwan (鎭管, regional garrison) system was established in the provinces. The Joseon government also attempted to establish the "farmer-soldier system" (byeongnong-ilchi, 兵農一致體制) based on the principle of universal conscription (gungmin gaebyeongje, 國民皆兵制). However, in practice, this principle was undermined. The yangban aristocracy were effectively exempt from military service, and members of the cheomin (lowest social classes) were excluded except when chosen for certain special units. Thus, the majority of the military consisted of yangin peasant farmers (良人農民). Meanwhile, the central army often included specialized soldiers recruited regardless of the farmer-soldier system. Their officers in the Joseon army came exclusively from the yangban, and the king appointed them. Still, they valued scholarship over war as something unworthy of a Confucian gentleman-scholar. The quality of Korean generals varies. Some Korean officers being able, and others being men who had not devoted much time to the study of war, preferred archery, writing, practicing their calligraphy, and reading Confucian classics. The military system of late Joseon can be characterized by the five main military camps (Ogunyeong, 五軍營) and the Royal Guards (Geumgun, 禁軍) in the capital, and by the Sogo Army (속오군,束伍軍) in the provinces. By the late 16th century, the early Joseon military system had nearly ceased functioning. Taking advantage of this weakness, the Japanese invaded, and the urgent need arose to reorganize and reform Joseon’s military institutions. To this end, the authority of the Border Defense Council (Bibyeonsa, 備邊司), which had been established in the 16th century to guard the frontiers, was strengthened.
=== Border Defense Council of Joseon === The Border Defense Council of Joseon was a supreme administrative organ established by the central government after the Disturbance of the Three Ports. It allowed the higher military officers, the Jibyeonsa Jaesang (지변사재상; 知邊司宰相), to participate in the process of establishing security maneuvers to meticulously keep a keen eye on the issues of the border.
=== Five Guards === Originally, troops of various arms were distributed under the Five Offices and 25 Commands, but the reorganization concentrated each type of troop into one of the Five Guards, thus unifying military functions rather than overall organization. The Owi (Five Guards) was the central military organization of early and mid-Joseon. Initially, after the dynasty’s founding, the central army inherited the 2 Armies and 6 Guards (igun-yukwi, 二軍六衛) system of late Goryeo, which was repeatedly reorganized into the 10 Guards (十衛), 10 Offices (十司), and 12 Offices (十二司). By 1451 it was consolidated into five commands and in 1457 this structure was formalized as the Owi. In 1469 (1st year of King Yejong), after further adjustments, the system was codified in the Gyeongguk Daejeon (National Code) under the authority of the Headquarters of the Five Guards (owi dochongbu, 五衛都摠府). This was based on Goryeo’s traditional "Five Army Battle Formation" (ogunjinbeop, 五軍陣法) and strengthened into a coherent structure. Each of the Five Guards consisted of five divisions (bu, 部), with one division based in Seoul and the others made up of provincial garrison forces. For example:
Uiheung Guard (義興衛, Central Guard): composed of elite armored troops (gapsa, 甲士) and supplementary troops. Yongyang Guard (龍驤衛, Left Guard): included special palace guards (byeolsiwi, 別侍衛). Hobun Guard (虎賁衛, Right Guard): included royal relatives’ guard units and close royal guard units. Chungjwa Guard (忠佐衛, Forward Guard): included loyalist and enemy-breaking units. Chungmu Guard (忠武衛, Rear Guard): included regular soldiers and brave warrior units. Troops were organized into 13 types of units, which fell into three categories:
Status-based privileged units (royal relatives, descendants of meritorious officials, high-ranking bureaucrats’ sons, etc.). Skill-based units (selected by martial arts examinations regardless of social status, e.g., gapsa, byeolsiwi, janggo wi). Duty-based peasant soldiers (ordinary peasant farmers fulfilling conscription, e.g., jeongbyeong, 正兵). This system applied to both central and provincial armies. Higher units were built in multiples of five, reaching the nationwide Five Guards = 25 Divisions = 100 Commands (tong, 統). However, ranks were not standardized, since unit membership was tied to social status rather than a professional rank hierarchy. The Owi combined standing troops like the Gapsa (armored soldiers), special guard units, and the regular conscript soldiers (jeongbyeong) formed the core under a rotation system, aligning both peacetime garrisons and wartime formations. Each guard oversaw specific regions of the capital and provinces, ensuring nationwide mobilization. At its peak, it fielded around 5,500 core soldiers plus auxiliary forces and maintained a complex officer hierarchy. However, by the late 16th century, the Owi weakened due to the spread of tax-in-lieu-of-service practices and was effectively replaced after the Imjin War (1592–1598) by the new Five Army Commands (Oguneong), leaving the Owi largely nominal.
=== Jeseungbangryak system === As service burdens grew, desertions increased. From the mid-15th century, the commutation system (Banggun Supoje, 放軍收布制) allowed men to pay cloth tax instead of serving, weakening the army. The state then adopted the Jesung Bangryak (制勝方略) strategy: during emergencies, all local troops gathered to resist under generals sent from the capital. It allowed the military commanders from the central government to control assembled troops from the main army to the local and provincial armies. But, local officers could not individually respond to a foreign invasion outside their jurisdiction until a higher ranking general, appointed by the king's court, arrived with a newly mobilized army. It was a highly inefficient arrangement since the nearby forces would remain stationary until the mobile border commander arrived on the scene and took control. Secondly, as the appointed General often came from an outside region. The general was unlikely unfamiliar with the natural environment, the available technology, and staffing of the invaded region. Finally, as the government never maintained the main army, new and ill-trained recruits conscripted during war constituted a significant part of the army.
=== Army units === In the Joseon Army, there are army units between the Jeon-gi (前期, "pre-period") and Hu-gi (後期, "post-period"). Jeon-gi is based on the Owi (오위) system established during the Munjong period.
=== Ranks === The highest rank of the army was the Dowonsu (都元帥). The Commander in chief of all 8 provinces' armed forces. A temporary rank, the rank that commanded the local army. The scope of the command is flexible. Although it was the highest rank, it is said that the number of troops that Dowonsu could actually command was considerably small due to the temporary performance that was only permanent during wartime and the command system that was not unified into one. The second highest rank was the Samdo Sunbyonsa, the Commander of three provinces – Kyongsang, Cholla and Chung Chong. The third highest rank was the Sunbyonsa, a provincial commander. The fourth highest rank was the Pangosa: a county commander defending strategic points.
Royal Guard
The Royal Guards of the Joseon Dynasty were an elite group of soldiers responsible for protecting the King and the royal family and defending the Geumjung (禁裏) (or Geumjung (禁中), the king's residence. They number up to 50–200 men tasked with guarding the palace and escorting the king. All were rigorously selected through martial arts tests, served without rotation, and received full stipends. These were under commanders called "inner generals" (naejang, 內將). They were divided into several different units, each with their own specific responsibilities. The Naegeumwi (內禁衛, Royal Inner Guards), founded in 1407, began as a small palace corps of 60–90 men but grew into 190 permanent guards supported by reserves, drawn mostly from yangban through strict exams, and served as the backbone of palace defense, though often also dispatched to frontier duty. The Gyemsabok (兼司僕, Mounted Guards), reorganized in 1464 from earlier mounted guard traditions, were an elite cavalry unit that prioritized martial skill over birth, allowing not only aristocrats but also secondary sons, commoners, outcasts, defected foreigners, and even Japanese to enlist if they passed rigorous tests; they enjoyed high ranks, land stipends, privileges, and opportunities for advancement. The Urimwi (羽林衛, Feathered Forest Guard), established in 1492 as a supplementary unit for marginalized aristocrats (illegitimate aristocratic offspring) to expand opportunities and compensate for guard shortages, numbered 50 permanent soldiers with official ranks and stipends, ranking below the Naegeumwi and Gyemsabok but above regular armored infantry, and though briefly abolished, were reinstated and later integrated into the Royal Guards Command. Together, these three corps—embodied both the exclusivity and adaptability of Joseon’s royal security system, balancing rigid hierarchy with avenues for social mobility through martial service. The Howicheong (扈衛廳) was created in 1623 after King Injo’s Restoration, essentially as a private guard for the coup leaders. Over time it grew into three divisions with over 1,000 officers, but under King Jeongjo (r. 1776–1800) it was reduced and reorganized into a loyal royal guard. Other temporary guard units (e.g., Cheongrodae, Jeonglowi) were also formed to reinforce royal authority.
=== Restriction Guard === In 1666, King Hyeongjong established the Restriction Guard (Geumgun) by integrating the Naegeumwi, Gyeomsabok, Woorimwi and the Jungrowi into the Office of the Restriction Guards (Geumguncheong). The Restriction Guard, also known as Geumgun in Korean, were a select group of highly trained soldiers who served as the personal bodyguards of the Joseon Dynasty's royal family. They were responsible for protecting the king and his immediate family members, as well as important government officials and palaces. The Restriction Guard members were selected from the most skilled and loyal soldiers in the kingdom. They underwent rigorous training in martial arts, archery, horseback riding, and other combat skills. In addition to their combat training, the Restriction Guard also received education in Confucianism, the dominant philosophy of the time. The members of the Restriction Guard were distinguished by their distinctive black uniforms and their use of black horses. They were also equipped with special weapons, such as the geom, a type of Korean sword, and the gakgung, a type of Korean bow. The Restriction Guard played an important role in maintaining order and stability within the kingdom, and they were known for their loyalty to the royal family and their willingness to sacrifice their lives in defense of the throne. The Office of the Restriction Guards, also known as Geumguncheong in Korean, was the administrative headquarters of the Restriction Guard during the Joseon Dynasty. It was responsible for overseeing the training, deployment, and management of the Restriction Guard. The Geumguncheong was located within the palace complex and was headed by a high-ranking government official known as the Geumgunjang, who was appointed by the king. The Geumgunjang was responsible for overseeing the day-to-day operations of the Restriction Guard and ensuring that it fulfilled its duties and responsibilities. The Geumguncheong was also responsible for managing the finances of the Restriction Guard, including its budget for weapons, equipment, and supplies. In addition, it played a key role in coordinating with other government agencies to maintain law and order within the kingdom. The Geumguncheong was an important institution in the Joseon Dynasty, as the Restriction Guard played a critical role in maintaining the stability of the kingdom and protecting the royal family.
=== Dragon Tiger Guard === In 1755, King Yeongjo renamed the Restriction Guard into the Dragon Tiger Guard (Yonghoyeong); its total number of members increased to 700. It was a special military unit in the Joseon Dynasty that was responsible for protecting the royal palace and the king's person. The name "Yonghoyeong" means "dragon tiger guard" and refers to the two mythical creatures that were believed to symbolize strength and power. Its members were selected from the most skilled soldiers in the kingdom. They underwent rigorous training in martial arts, archery, and other combat skills, as well as in the use of firearms, which were introduced to Korea during this period. The Dragon Tiger Guard was distinguished by its distinctive red uniforms and its use of red banners and flags. Its members were also equipped with special weapons, such as matchlock muskets and bamboo spears. The Dragon Guard played a critical role in maintaining the security of the royal palace and the king's person, as well as in suppressing rebellions and maintaining law and order throughout the kingdom. Its members were known for their bravery, loyalty, and martial prowess, and they were considered to be among the most elite soldiers in the Joseon Dynasty.
=== Royal Elite Camp === In 1793, King Jeongjo established the Royal Elite Camp (Jangyongyeong). It was briefly an inner-outer guard system intended to serve as a standing army that could be deployed quickly to defend the kingdom in times of crisis. The Jangyongyeong Guard was named after a famous military treatise written during Goryeo, which emphasized the importance of military training and discipline. The soldiers in the Jangyongyeong Guard underwent rigorous training in martial arts, archery, and other combat skills, and they were equipped with modern firearms, such as muskets and rifles. Unlike the Restriction Guard and the Dragon Guard, which were composed of soldiers from the aristocracy, the Jangyongyeong Guard was open to commoners who demonstrated exceptional martial skills and loyalty to the king. This was a significant departure from the traditional social hierarchy of Joseon, which placed a premium on aristocratic birth and education. The Jangyongyeong Guard also played a role in suppressing domestic rebellions and maintaining law and order throughout the kingdom. The establishment of the Jangyongyeong Guard was one of King Jeongjo's most significant military reforms, and it helped to modernize and strengthen Joseon's military capabilities. This unit disbanded under King Sunjo as royal authority weakened.