Gwanggaeto the Great of the Goguryeo Kingdom (northern Korea) ruled from 391 to 413 CE. During that period, he vastly expanded the borders of the Goguryeo Kingdom, forcing the other Korean kingdoms (Silla and Baekje) as well as many neighboring peoples to become his tributaries.
After Gwanggaeto died, his son ordered a 7-meter tall stele, inscribed with more than 1800 classical Chinese characters, to mark the site of the king's grave. The inscription, which was rediscovered in 1875, reveals a lot of information about Gwanggaeto's reign.
Note: The personal and place names are speculative. Ellipses indicate missing or illegible sections.
"Long time ago, the first king Chumo established the country. He was born in North Buyeo. His father is the Emperor of the Heavens and mother's name is Habaek. He cracked the eggshell and [stepped down to this world]. He was innately the monarch [of virtue who]. . . . . .(He) went [a round in the country riding on a carriage], through Buyeo and Eomri Daesu River, to the south. At a bank of the Bullyu Cave, he said, "I am the King Chumo. My father is the Emperor of the Heavens and mother is Habaek. Turtles, float and form a line for me!" In the answer to his voice, innumerable turtles floated in a row to let him cross the river. He built the capital on the Seongsan Mountain in the west of Holbon.
[Since] the country seemed [stable and tranquil for a long time], a messenger (of the God), a golden dragon came down to invite him to the Heavens. On a hill in the east of Holbon, the king ascended to the heaven [on] the [golden] dragon's [back of the neck]. According to Chumo's will, King Yuryu ruled the country thereafter, and then King Daejuryu succeeded.
The 17th King is the Gukgangsang Gwanggaeto Gyeongpyeongan Hotae Wang. He ascended the throne at age of 18 and his throne title is the "King Yeongrak the Great". His merciful heart [was like] the Emperor of the Heavens, and his dignity and bravery swayed the four oceans. He swept away [all the anxieties] and securely ruled the country. The nation was wealthy, people were prosperous, the harvest was abundant, and the sky was clear without calamities.
He [abdicated the throne] at age of 39 [by his death]. As of Eul'yu day September 29, Gap'in year (CE 411), this stone monument is set up for his mountain tomb with inscription of his achievements to pass it [eternally] down to posterity:
Year of Yeongrak 5 (CE 395), Eulmi:
Since Paryeo tribe did not [stop xxx-ing], the King led troops to subjugate them [again]. Passing through Bu and [Dap] mountains, the King's troops reached by the Yeomsu River and defeated Paryeo's [military] fort with troops of 600-700 strong. There were countless cows, horses and sheep. On his return trip, the King inspected through the states passing through [Gok]pyeong-do, Dongrae[hu Castle], Ryeok Castle, Bukping and [Obihae], and did a hunting before returning in triumph.
Since Baekjan and Silla are originally subservient states (of Goguryeo), they paid tributes (to Goguryeo). And since the Sinmyo year (CE 391), the Wa (Japanese) came across the sea, defeated Baekjan, [(then xxx-ed Sil]la and made them subjects.
In Yeongrak 6 Hyeongsin year (CE 396), the King led [navy] troops to [punish] Baekjan. The troops conquered [(Baekjae's) provincial] castles of Ilpal, Gumono, [Gak]mono, Gandaeri, [xxx], Gakmi, Mono, Misa, [Gosa]yeon, Adan, Gori, [xx]-ri, Jap[jin], Ori, Homo, Go[mo]yara, [Makchu], [xxx], [Bu]niyara, [Yeon], [Eori], [Nongmae], Duno, Bul[palbi]-ri, Michu, Yari, [Dae]sanhan, Soga, Donbal, [xxx], [Rumai], [San'na], [Naru], Se, Moru, Uru, Sohoe, Yeonru, [Seo]jiri, Am-mun[ji], Lim, [xxx], [xxx], [xx-ri], Chwichu, [xx]bal, Gomoru, Yun'no, Gwan'no, Pungyang, [Bobal], [Jon'go]ra, Gucheon, [xxx].
The rebels (Baekje) still disobeyed and defied to have a [total] war. It made the king enraged. He led troops crossing the Arisu moat and closed in on the castle. They [made an attack from the flank, destroyed castle walls], and quickly [besieged] the castle. [Now] (Baek)jan [king] was driven into a corner and offered 1,000 people [as captives] and 1,000 pil (?) of fabrics, then himself swore to be obedient to become a subject (of Goguryeo) forever. The King Gwanggaetto granted amnesty to the (Baekjae King's) frenzied blunders in the past and wrote down the (Baekje King's) oath as the "Faith of submission.” Accordingly, the Great King [acquired] 58 castles, 700 village towns and returned to the capital in triumph with (Baek)jan [king's] younger brother and 10 nobles (as hostages).
Yeongrak 8 Musul year (CE 398):
King sent a troop to scout a tribe of Sushen. It resulted to have a tiny profit of capturing the Maksilla Castle and seizing the 300 Taera-gok Cave people. Since then, they have sent tribute (to Goguryeo).
Yeongrak 9 Gihae year (CE 399):
Baekjan broke the previous promise and allied with Wa. The King advanced to Pyongyang. There he saw Silla's messengers telling him, "There were full of the Wa troops around the border and the castle's moat was filled in. Since we are servants of Your Majesty, we pledge our allegiance to you and cordially ask your help." The King mercifully [praised] their allegiance and let the messengers return (to Silla) [with his secret] message [of a stratagem].
Yeongrak 10 Gyeongja year (CE 400):
The King sent 50,000 troops to save Silla. From the Namgeo Castle to the Silla Castle (Silla capital?), these castles were [full up with] the Wa troops. When Goguryeo [soldiers] arrived, the Wa troops retreated......(the Goguryeo troops) [hurried] to chase after (the Wa troops) to Imna Gara. When they assaulted the castle, the castle yielded immediately. (Meanwhile), the Alla defense soldiers [attacked] the Silla [Castle being full up with] the Wa troops. The Wa annihilated the castle and greatly......[although the 90 percent in the castle] were killed, [they rejected to surrender and these Alla soldiers were seized in the (Sil)la Castle]......the [castle town was especially]...... The granite is crumbled away here, and much of the inscription is lost.......[a correspondence of]......[at the dawn]......[the Wa soldiers]......[small]......[occurred]......declined......[the (Baek)jan and the Wa]......annihilated, the Alla soldiers [of the Castle were also]...
Until that time, [the Prince] of Silla never appeared (to Goguryeo) by himself to [discuss on matters. The King Gukgangsang Gwang]gaeto Gyeongpyeongan Hotae [xxx-ed Silla so that the Prince] Bokho [of the xxxx house petitioned] to pay [a thousand of xxxx for] tribute (to Goguryeo).
Youngrak 14 Gapjin year (CE 404):
The Wa unexpectedly invaded the southern border at Daifang. [The Wa allying with the (Baek)jan soldiers reached] the Seok Castle. Their [xxx] fleet...... [The King himself led troops from] Pyongyang [to defeat them]......[colliding] each other. The (Goguryeo) swordsmen with the King's flag slashed at the enemies and the Wa pirate collapsed with enormous casualties.
Youngrak 17 Jeongmi year (CE 407):
The King sent 50,000 troops to (defeat?)......[the King's army] battled [all around], and entirely killed the troops. The triumphant force [acquired] over 10,000 armors and enormous amount of military equipment with recapturing six castles of Sagu, Ru, [Hwanju], [xxx], [xxx], [xxnaxx].
Youngrak 20 Gyeongsul year (CE 410):
Among subservient states since the time of the King Chumo, only East Buyeo was disobedient and did not pay tribute (to Goguryeo). The King led troops to subjugate them. When the troops arrived at the Yeo Castle, they [were surprised and became obedient, and]......, the King mercifully decided to refrain from [overthrowing them] and he returned home. There were also (five) nobles, Miguru, Bisama, [Danrip]ru, Suksasa and [xxx] following after the King (to Goguryeo) as they submitted to the King's august virtue. The number of conquered castles is 64 and villages are 1,400."
Father's Manifesto, "Gwanggaeto Stele Translation."