Sejong the Great (May 6, 1397 – May 18, 1450, r. 1418 - 1450) was the fourth
king of the Choson Dynasty of Korea. He is best remembered for creating
the native Korean alphabet Hangul, despite strong opposition from the
scholars educated in hanja (Chinese script). Sejong is one of only two
Korean rulers posthumously honored with the appellation "the Great," the
other being Gwanggaeto the Great of Goguryeo.
Early life
Sejong was the third son of King Taejong. When he was sixteen, he became
Grand Prince Chungnyeong  and married a daughter of Sim On of
Cheongsong , commonly known as Lady Sim  who later was given the title
Princess-Consort Soheon.
As a young prince, Sejong excelled in various studies and was favored by
King Taejong over his two older brothers.
Sejong's rise to the throne was different from most other kings. The eldest
prince, Yangnyung (양녕대군), viewing himself as lacking in the requisite
skills for kingship, believed that Sejong was destined to become king.
Together with the second prince Hyoryung, he believed it was their duty to
place Sejong as king. So they acted extremely rudely in the court, and soon
were banished from Seoul. This ploy of the two princes ultimately brought
Sejong to the throne. The eldest prince became a wandering traveler and
lived in the mountains. The second son travelled to a Buddhist temple,
where he became a monk.
In June 1418, King Taejong abdicated and Sejong was crowned King of
Joseon (in August of the same year) and began his rule. (Taejong helped in
military as ex-king for 4 years, and died in 1422)

Hangul
King Sejong the Great made a great impact on Korean history with his
introduction of Hangul, the native phonemic alphabet system for the Korean
language.
Before the creation of Hangul, only members of the highest class were
literate. Hanja, the written language of that time, represented the Korean
spoken language by using Chinese characters. One would have to learn the
Chinese language in order to read and write with Hanja. Cumbersome, it
disadvantaged the lower classes.
King Sejong presided over the introduction of the 28 letters of the Korean
alphabet in order that Koreans from all classes could read and write. He also
attempted to establish a cultural identity of his people because they had
their own written language. First published in 1446, anyone could learn
Hangul in a matter of days, and although banned 60 years later it
experienced a revival in post-WWII Korea where it enjoys widespread usage
today.

Strengthening of Korean Military
King Sejong was an effective military planner. During his era, he sent an
army to destroy the increasing number of Japanese pirates appearing on
Korean shores. Naval engagements quieted much pirate activity, and led to
the invasion of the Japanese island of Tsushima. Korea controlled the island
after this and Korean civilians were allowed to live in Tsushima. After King
Sejong's rule, however, Tsushima fell back into Japanese control.
On the northern border, he established four forts and six posts (Hangul :
Hanja :to safeguard his people from the hostile Chinese and Manchurian
nomads living in Manchuria. He also created various military regulations to
strengthen the safety of his kingdom. King Sejong supported the
advancement of Korean military technology and cannon development
increased. Different kinds of mortars and fire arrows were tested as well
using gunpowder.
In 1433, Sejong sent Kim Jong-seo, a prominent general, north to destroy the
Manchu. Kim's military campaign captured several castles, pushed north,
and restored Korean territory, roughly the present-day border between North
Korea and China.

Literature
Sejong overall, supported literature, and encouraged high class officials and
scholars to study at the court. King Sejong also oversaw the creation of
Hangul and announced it to the Korean people in the Hunminjeongeum,
which was an announcement composed of both Hangul and Hanja.
Although most of the government officials and the aristocracy opposed the
usage of Hangul, lower classes embraced it, became literate, and were able
to communicate among one another easily.
Sejong's personal writings are also highly regarded. He composed the
famous Yongbi Eocheon Ga (“Songs of Flying Dragons”, 1445), Seokbo
Sangjeol (“Episodes from the Life of Buddha”, July 1447), Worin Cheon-gang
Jigok (“Songs of the Moon Shining on a Thousand Rivers”, July 1447), and
the reference Dongguk Jeong-un (“Dictionary of Proper Sino-Korean
Pronunciation”, September 1447).
Sejong established the Hall of Worthies Jiphyeonjeon) in 1420 in the royal
palace, Sejong gathered intellectuals from around Korea. The scholars of the
Hall of Worthies documented history, drafted documents and compiled
books on various topics. Korea culturally advanced through King Sejong's
encouragement.
Following the principles of Neo-Confucianism, Sejong was also a
humanitarian who proclaimed that there must be three trials before a final
judgment is reached, and he prohibited brutality in the punishment of
criminals, such as flogging.

Technology
Sejong is also credited with technological advances during his reign. During
his rule, Jang Yeong-sil (also, Chang Yongsil), who worked for the Palace
Guard, became known as a prominent inventor. Jang was naturally a creative
and smart thinker as a young person. However, Jang was at the bottom of
the social class. Sejong noticed Jang's skill and immediately called him to
his court in Seoul. Upon giving Jang a government position and power to
invent anything, the officials protested, believing that a low class person
could not rise to power as a noble or a higher class. Sejong instead believed
that Jang had the skill and supported his projects.
Jang invented the world's first rain gauge and created some significant water
clocks and sundials.
King Sejong wanted to help the farmers so he decided to create the farmer's
handbook. The book contained information about the different farming
techniques that he told the scientists to gather in different regions in Korea.
Depending on the land of the farmers, he allowed them to pay more or less
taxes. By this action, many farmers had fewer worries about keeping alive.
Once the palace had a surplus of food, King Sejong shared the food with the
poor peasants or farmers who needed it.

End of Reign 1450
Sejong died at the age of 53 and was buried at the Yeong Mausoleum  in
1450. His successor was his first son, Munjong.
The street Sejongno and the Sejong Center for the Performing Arts – both
located in central Seoul – are named after King Sejong, and he is depicted on
the South Korean 10,000-Won note.

Family
Father: King Taejong
Mother: Queen Wongyeong  
Consorts:
Queen Soheon
Children:
King Munjong , 1st Son.
Grand Prince Su-yang, 2nd Son. later King Sejo.
Grand Prince Anpyeong, 3rd Son.
Grand Prince Im-yeong , 4th Son.
Grand Prince Gwangpyeong, 5th son.
Grand Prince Gumseong, 6th son.
Grand Prince Pyeongwon, 7th son.
Grand Prince Youngeung, 8th son.
Princess Jeongso, 1st daughter.
Princess Jeong-eui, 2nd daughter.
Se-Jong Illustrated
CLOSED
READY
STANCE B
Move the left
foot to B,
forming a left
walking stance
toward B at the
same time
executing a low
block to B with
the left forearm.
Bring the left
foot to the right
foot, and then
move the right
foot to A to form
a left L-stance
toward A while
executing a twin
forearm block.
Execute a middle
side piercing kick
to D with the right
foot.
Lower the right
foot to D, and
then move the
left foot to F to
form a left
walking stance
toward F while
executing a
rising block with
the left forearm.
Bring the left
foot to the right
foot, and then
move the right
foot to E to form
a sitting stance
toward D while
executing a
middle strike to
E with the right
knife-hand.
Bring the right
foot to the left
foot, forming a
closed ready
stance B toward
D.
Jump to D to form
a left X-stance
toward DG while
executing a high
side strike to D with
the left back fist,
bringing the right
finger belly to the
left side fist.
Move the right
foot to G,
forming a right
walking stance
toward G while
executing a high
punch to G with
the right fist.
Move the right
foot on line GH to
form a left fixed
stance toward H
while executing a
high guarding
block to H with
the forearm.
Move the right foot
to H, forming a
right walking
stance toward H
while executing a
middle thrust to H
with the right
straight finger tip.
Bring the right
foot to the left
foot, and then
move the left foot
to G to form a left
walking stance
toward G while
executing a high
side strike to G
with the left back
fist.
Move the left
foot on line GH
to form a sitting
stance toward
C while
executing a
scooping block
with the left
palm.
Execute a
middle turning
kick to C with the
left foot.
Lower the left foot
to C in a jumping
motion, forming a
left X-stance
toward CF while
executing a high
block to C with the
left double
forearm.
Move the right foot
to F to form a
sitting stance
toward C while
extending the right
fist horizontally to
C. Perform in a
slow motion.
Execute a front
strike to C with
the left back fist
while
maintaining a
sitting stance
toward C.
Bring the right
foot behind the
left foot, and then
move the left foot
to E, forming a left
diagonal stance
toward C while
executing a
pressing block
with a twin palm.
Execute a middle
block to C with a
double arc-hand
while forming a
left walking
stance toward CE.
Pull the left
reverse
foot-sword to the
right knee joint to
form a right
one-leg stance
toward C at the
same time
executing a high
side block to F
with the right
outer forearm and
a low side block to
E with the left
forearm.
Lower the left foot
to D forming a
right walking
stance toward C
while executing a
pressing block
with the right
palm. Perform in
a slow motion.
Pull the left
instep to the
hollow of the
right leg to form
a right one-leg
stance toward C
while striking the
left palm with the
right back
forearm.
Lower the left foot
to C, turning
clockwise to form
a right fixed
stance toward D
while thrusting to
C with the left side
elbow.
Move the right
foot to A, forming
a left L-stance
toward A while
executing a high
guarding block to
A with a
knife-hand.
Bring the right foot
to the left foot, and
then move the left
foot to B to form a
right L-stance
toward B while
executing a middle
punch to B with
the right fist.
Bring the left
foot back to a
ready posture.
SE-JONG
Movements - 24
Ready Posture - CLOSED READY STANCE B

Pattern Meaning
SE-JONG is named after the greatest Korean King, Se-Jong, who
invented the Korean alphabet in 1443, and was also a noted
meteorologist. The diagram represents the king, while the 24
movements refer to the 24 letters of the Korean alphabet.
V