Biography

Historical context for rise

By the late 14th century, the 400-year-old Goryeo dynasty established by Wang Geon in 918 was tottering, its foundations collapsing from years of war and de facto occupation by the waning Yuan dynasty. The legitimacy of Korea itself was also becoming an increasingly disputed issue within the court, as the ruling house failed not only to govern the kingdom effectively, but was also tarnished by generations of forced intermarriage with members of the Yuan imperial family and by rivalry amongst various Goryeo royal family branches (even King U's mother was a known commoner, thus leading to rumors disputing his descent from King Gongmin).

Within the kingdom, influential aristocrats, generals, and even prime ministers struggled for royal favor and vied for domination of the court, resulting in deep divisions among various factions. With the ever-increasing number of raids against Goryeo conducted by Japanese pirates (wakō) and the Red Turbans, those who came to dominate the royal court were the reformed-minded Sinjin aristocracy and the opposing Gweonmun aristocracy, as well as generals who could actually fight off the foreign threats—namely a talented general named Yi Seong-gye and his rival Choe Yeong. With the rise of the Ming dynasty under a former monk, Zhu Yuanzhang (the Hongwu Emperor), Yuan forces became more vulnerable. By the 1350s Goryeo regained its full independence from the Yuan dynasty, although Yuan remnants effectively occupied northeastern territories with large garrisons of troops.

Military career

General Yi Seong-gye had gained power and respect during the late 1370s and early 1380s by pushing Mongol remnants off the peninsula and also by repelling well-organized Japanese pirates in a series of successful engagements. He was also credited with routing the Red Turbans when they made their move into the Korean Peninsula as part of their rebellion against the Yuan Dynasty. Following in the wake of the rise of the Ming dynasty under Zhu Yuanzhang, the royal court in Goryeo split into two competing factions: the group led by General Yi (supporting the Ming dynasty) and the camp led by his rival General Choe (supporting the Yuan dynasty).

When a Ming messenger came to Goryeo in 1388 (the 14th year of King U) to demand the return of a significant portion of Goryeo's northern territory, General Choe seized the opportunity and played upon the prevailing anti-Ming atmosphere to argue for the invasion of the Liaodong Peninsula (Goryeo claimed to be the successor of the ancient kingdom of Goguryeo; as such, restoring Manchuria as part of Korean territory was a tenet of its foreign policy throughout its history).

A staunchly opposed Yi was chosen to lead the invasion; however, at Wihwa Island on the Amrok River, he made a momentous decision, commonly called "Turning back the army from Wihwa Island", that would alter the course of Korean history. Knowing of the support, he enjoyed both from high-ranking government officials, the general populace, and the great deterrent of Ming Empire under the Hongwu Emperor, he decided to revolt and swept back to the capital, Gaegyeong, to secure control of the government.

Revolution

General Yi swept his army from the Yalu river straight into the capital, defeated forces loyal to the king (led by General Choe, whom he proceeded to eliminate), and forcibly dethroned King U in a de facto coup, but did not ascend to the throne right away. Instead, he placed on the throne King U's son, King Chang, and following a failed restoration of the former monarch, had both of them put to death. General Yi, now the undisputed power behind the throne, soon forcibly had a Goryeo royal named Yo, now King Gongyang (공양왕; 恭讓王), crowned as king. After indirectly enforcing his grasp on the royal court through the puppet king, Yi then proceeded to ally himself with Sinjin aristocrats, such as Jeong Do-jeon and Jo Jun. In 1392 (the 4th year of King Gongyang), Yi dethroned King Gongyang, exiled him to Wonju (where he and his family were secretly murdered), and ascended the throne, thus ending the Goryeo Dynasty after 475 years of rule.

One of the most widely repeated episodes that occurred in the immediate aftermath of the fall of Goryeo was in 1392, when Taejo's fifth son, Yi Bang-won (later King Taejong), threw a party for the renowned scholar, poet and statesman Jeong Mong-ju, who refused to be won over by Yi despite their numerous correspondences in the form of archaic poems, and continued to be a faithful supporter of the old dynasty, and a leading figure in the opposition to Yi's claim to the throne. Jeong was revered throughout Goryeo, even by Yi Bang-won himself, but he was seen to be an obstacle and as such, in the eyes of supporters of the new dynasty, had to be removed. After the party, on his way home, Jeong was murdered by five men on the Seonjuk Bridge (선죽교; 善竹橋) in Gaeseong. This bridge has now become a national monument of North Korea, and a brown spot on one of the stones is said to be a bloodstain of his which turns red when it rains.

Reign

Yi Seong-gye declared a new dynasty in 1392–1393 under the name of Joseon, thereby reviving an older state, also known as Joseon (Gojoseon), that was, legendarily, established nearly three thousand years previously, and renamed the country the "Kingdom of Great Joseon".

An early achievement of the new monarch was improved relations with China; and indeed, Joseon had its origin in General Yi's refusal to attack China in response to raids from Chinese bandits. Shortly after his accession, the new monarch sent envoys to inform the Ming court at Nanjing that a dynastic change had taken place. Korean envoys were dispatched to Japan, seeking the re-establishment of amicable relations. The mission was successful; and shōgun Ashikaga Yoshimitsu was reported to have been favorably impressed by this initial embassy. Envoys from the Ryūkyū Kingdom were received in 1392, 1394 and 1397. Siam sent an envoy in 1393.

In 1394, the capital was established at Hanseong (Seoul). When the new dynasty was promulgated and officially brought into existence, Taejo brought up the issue of which son would be his successor. Although Taejo's fifth son by Queen Sineui, Yi Bang-won, had contributed most to assisting his father's rise to power, he harbored a profound hatred against two of his father's key allies in the court, the prime minister Jeong Do-jeon and Nam Eun.

Both sides were fully aware of the mutual animosity that existed between each other and constantly felt threatened. When it became clear that Yi Bang-won was the most worthy successor to the throne, Jeong Do-jeon used his influence on the king to convince him that the wisest choice would be in the son that Taejo loved most, not the son that Taejo felt was best for the kingdom.

In 1392, the eighth son of King Taejo (the second son of Queen Sindeok), Grand Prince Uian (Yi Bang-seok) was appointed Prince Royal, or successor to the throne. After the sudden death of the queen, and while King Taejo was still in mourning for his second wife, Jeong Do-jeon conspired to pre-emptively kill Yi Bang-won and his brothers to secure his position in court.

In 1398, upon hearing of this plan, Yi Bang-won immediately revolted and raided the palace, killing Jeong Do-jeon, his followers, and the two sons of the late Queen Sindeok. This incident became known as the First Strife of Princes. Aghast at the fact that his sons were willing to kill each other for the crown, and psychologically exhausted from the death of his second wife, King Taejo immediately crowned his second son Yi Bang-gwa, later King Jeongjong, as the new ruler. Thereafter, King Taejo retired to the Hamhung Royal Villa. After that, he maintained distance with Yi Bang-won. Doing so provoked huge rampage from Taejo, because both the two sons and Jeong Do-jeon were whom he favored. Allegedly, Yi Bang-won sent emissaries numerous times, and each time Taejo killed them to express his firm decision not to meet his son again. This historical anecdote gave birth to the term "Hamhung Cha sa", which means a person who never comes back despite several nudges. But recent studies have found that Taejo in fact did not kill any of those Hamung emissaries. Those subjects were killed during revolts, which coincidentally occurred in the Hamhung region.

In 1400, King Jeongjong pronounced his brother Yi Bang-won as heir presumptive and voluntarily abdicated. That same year, Yi Bang-won assumed the throne of Joseon at long last as King Taejong.

Ten years after his abdication, King Taejo died on May 24, 1408 in Changdeok Palace. He was buried at the tomb of Geonwonleung (건원릉, 健元陵) in the city of Guri.

Genealogy

Ancestors

Family

One of the many issues demonstrating the early strained relationship between the early Joseon and Ming was the debate of Taejo's genealogy, which began as early as 1394 Sillok, vol.6, July 14, 1394, entry 1 and became a sort of diplomatic friction that lasted over 200 years. The Collected Regulations of the Great Ming (then known as 大明會通 Dà Míng Hùitōng) erroneously recorded "Yi Dan" (이단; Taejo's original name) as the son of Yi In-im (이인임), and that "Yi Dan" killed the last four kings of Goryeo, thereby establishing Ming's opinion of Taejo as an usurper first and foremost, from the time of the Hongwu Emperor when he repeatedly refused to acknowledge him as the new sovereign of the Korean peninsula (1373-1395). The first mention of this error was in 1518 (about 9 years after the publication; Jungjong Sillok, vol.32, June 3, 1518, entry 1), and those who saw the publication wrote petitions towards Ming demanding for redress, among others Fourth State Councillor (좌찬성) Lee Gye-maeng (이계맹) & then-Minister of Rites (예조판서) Nam Gon, whose petition "Jong'gye Byeonmu" (종계변무 宗系辨誣) Sillok, vol.33, July 3, 1518, entry 1 took until 1584 (after many Ming envoys had seen it), through Chief Scholar (대제학) Hwang Jeong-uk (황정욱), that the issue was finally addressed Seonjo Sillok, December 2, 1584, entry 2]; the Wanli Emperor commissioned a second edition in 1576 (covering the years covers the years between 1479 and 1584). About a year after its completion, Yoo Hong (유홍) saw the revision, and returned to Joseon with the good news Sillok, vol.22, April 23, 1588, entry 1; May 19, 1588, entry 1.

• Father: King Hwanjo of Joseon (1315 – January 1, 1361) (조선 환조) (이자춘, 1315-January 1361)

　• Grandfather: King Dojo of Joseon (? – 1342) (조선 도조)

　• Grandmother: Queen Gyeongsun of the Munju Park clan (경순왕후 박씨)

• Mother: Queen Uihye of the Yeongheung Choi clan (의혜왕후 최씨)

　• Grandfather: Choi Han-Gi (최한기)

　• Grandmother: Lady Joseonguk of Lee clan (조선국대부인 이씨)

• Consorts and their Respective Issue:

• Queen Shinui of the Anbyeon Han clan (September 1337 – October 21, 1391) (신의왕후 한씨)

• # Yi Bang-U, Grand Prince Jinan (1354 - January 15, 1394) (이방우 진안대군)

• # Yi Bang-Gwa, Grand Prince Yeongan (July 18, 1357 – October 15, 1419) (이방과 영안대군)

• # Yi Bang-Ui, Grand Prince Ikan (1360 – September 26, 1404) (이방의 익안대군)

• # Yi Bang-Gan, Grand Prince Hwoean (July 2, 1364 – April 10, 1421) (이방간 회안대군)

• # Yi Bang-Won, Grand Prince Jeongan (June 13, 1367 – May 30, 1422) (이방원 정안대군)

• # Yi Bang-Yeon, Grand Prince Deokan (이방연 덕안대군)

• # Princess Gyeongshin (? – April 29, 1426) (경신공주)

• # Princess Gyeongseon (경선공주)

• Queen Sindeok of the Goksan Kang clan (July 12, 1356 – September 15, 1396) (신덕왕후 강씨)

• # Yi Bang-Beon, Grand Prince Muan (1381 - October 6, 1398) (이방번 무안대군))

• # Yi Bang-Seok, Grand Prince Uian (1382 – October 6, 1398) (이방석 의안대군)

• # Princess Gyeongsun (? – September 8, 1407) (경순공주)

• Royal Noble Consort Seong of the Wonju Won clan (? – December 29, 1449) (성비 원씨)

• Lady Jeonggyeong of the Goheung Yu clan (정경궁주 유씨)

• Princess Hwaui of the Kim clan (? – 1428) (화의옹주 김씨)

• # Princess Sukshin (? – 1453) (숙신옹주)

• Lady Chandeok of the Ju clan (찬덕 주씨)

• # Princess Uiryeong (? – February 1, 1466) (의령옹주)

His full posthumous name

• King Taejo Jiin Gyewun Seongmun Shinmu the Great of Joseon

　• 태조지인계운성문신무대왕

　• 太祖至仁啓運聖文神武大王

• King Taejo Kangheon Jiin Gyewun Seongmun Shinmu the Great of Joseon

　• 태조강헌지인계운성문신무대왕

　• 太祖康獻至仁啓運聖文神武大王

• Emperor Taejo Jiin Gyewun Eungcheon Jotong Gwanghun Yeongmyeong Seongmun Shinmu Jeong'ui Gwangdeok of the Korean Empire

　• 태조지인계운응천조통광훈영명성문신무정의광덕고황제

　• 太祖至仁啓運應天肇統廣勳永命聖文神武正義光德高皇帝

Legacy

The tomb of his Umbilical cord is in Man-In-san, Geumsan-gun, South Chungcheong Province in the Republic of Korea.

Despite the fact that he overthrew the kingdom of Goryeo, and purged officials who remained loyal to the old regime, many regard him as a revolutionary and a decisive ruler who deposed the inept, obsolete and crippled governing system to save the nation from many foreign forces and conflicts.

Safeguarding domestic security led the Koreans to rebuild and further discover their culture. In the midst of the rival Yuan and Ming Dynasties, the Joseon Dynasty encouraged the development of national identity which once was threatened by the Mongols. However, some scholars, particularly in North Korea, view him as a mere traitor to the old regime, paralleling him to a bourgeois apostate, and General Choe Yeong as a military elite, who conservatively served the old regime of Goryeo to death.

His diplomatic policy successes in securing Korea in the early modern period is notable.

Portrayals in adaptations

• Portrayed by Im Dong-jin in the 1983 KBS TV series Foundation of the Kingdom.

• Portrayed by Kim Mu-saeng in the 1983 MBC TV series The King of Chudong Palace and in the 1996 KBS TV series Tears of the Dragon.

• Portrayed by Lee Jin-woo in the 2005-2006 MBC TV series Shin Don.

• Portrayed by Oh Jae-moo in the 2012 SBS TV series Faith.

• Portrayed by Ji Jin-hee in the 2012-2013 SBS TV series The Great Seer.

• Portrayed by Yoo Dong-geun in the 2014 KBS1 TV series Jeong Do-jeon.

• Portrayed by Lee Dae-yeon in the 2014 film The Pirates.

• Portrayed by Lee Do-kyung in the 2015 JTBC TV series Maids.

• Portrayed by Son Byong-ho in the 2015 film Empire of Lust.

• Portrayed by Chun Ho-jin in the 2015-2016 SBS TV series Six Flying Dragons.

• Portrayed by Kim Ki-hyeon in the 2016 KBS1 TV series Jang Yeong-sil.

• Portrayed by Kim Yeong-cheol in the 2019 JTBC TV series My Country.

• Featured in Rise of Kingdoms, an android/iOS mobile game, as a playable character.

生平

開創基業

元順帝至元元年（1335年）十月十一日，李成桂出生在吾魯思不花的咸州私邸。高祖父李安社、曾祖父李行里、祖父孛顏帖木兒、伯父塔思不花、父吾魯思不花，世襲元朝斡東千戶所千戶兼達魯花赤。吾魯思不花歸附高麗後，回複高麗名李子春，官至榮祿大夫判將作監事、朔方道萬戶兼兵馬使。

李成桂二十二歲，也就是李子春歸附高麗的當年（1356年），出仕高麗。李成桂父子和高麗裡應外合攻取雙城總管府。1361年，萬戶樸儀叛亂，被李成桂率1500人鎮壓。同年紅巾軍侵略高麗，李成桂在開城率2000人擊敗紅巾軍。並在雙城總管府擊敗元軍。1362年2月、7月李成桂任東北面兵馬使擊敗元朝軍閥納哈出。1364年擊敗依附元朝的高麗反政府者崔儒。同年2月、侵入和寧（今咸鏡南道永興、現在的金野郡）以北討伐女真。1370年以騎兵五千步兵一萬自東北面渡鴨綠江攻打東寧府。北元東寧府同知李吾魯帖木兒逃往于羅山城。李成桂一度到達遼陽。

因軍功得幸于高麗恭愍王，官至密直副使，進階奉翊大夫，賜端誠亮節翊戴功臣之號。

1377年在智異山殲滅倭寇名聲大震，同年8月在西海道（黃海道）一帶大破倭寇。1380年倭寇500隻船侵入雲峰（全羅北道南原郡）占領引月驛、高麗敗北，駐紮在當地的將軍陣亡。李成桂被任命總指揮官擊敗倭寇首領阿只拔都（）。

1382年，明朝命故元降將胡拔都深入到東女真地區，招撫當地的女真人等。翌年八月，胡拔都又率部進抵端州，女真首領金同不花降附，高麗命令其大將李成桂率兵出擊，雙方戰于吉州平，女真敗退。

洪武二十一年（1388年），明朝在原雙城總管府之地設置鐵嶺衛，移文告知高麗。高麗國王王禑、門下侍中崔瑩密議進攻遼東，守門下侍中李成桂反對無效。是年四月，王禑派左軍都統使曹敏修、右軍都統使李成桂出兵攻遼。五月，曹敏修、李成桂渡過鴨綠江後，發覺行軍困難、糧餉不濟，上書要求班師，王禑不聽。于是發動威化島回軍，回師松都，流放崔瑩。六月，王禑退位，其子王昌即位。以李成桂為東北面朔方、江陵道都統使，賜忠勤亮節宣威同德安社功臣之號；八月，都總中外諸軍事；十月，兼判尚瑞司事。

洪武二十二年（1388年）十一月，王禑意圖複闢，事敗，李成桂以明朝稱王昌非恭愍王之後而不許入朝為藉口，廢王昌為庶人，改立高麗宗室王瑤，是為恭讓王。王禑流放江陵，王昌流放江華，十二月被誅。恭讓王以李成桂為奮忠定難匡複燮理佐命功臣，爵和寧君、開國忠義伯，食邑一千戶，食實封三百戶，田二百結、奴婢二十口，稱中興功臣，父母妻封爵，子孫蔭職。

洪武二十五年（1392年）七月十二日，右侍中裴克廉等脅迫恭愍王妃廢黜恭讓王。十七日丙申，在右侍中裴克廉、判三司事趙浚、奉化郡忠義君鄭道傳、同知密直司事南訚等親信的勸進下，李成桂在松都壽昌宮即位，時年五十八歲。

洪武二十七年（1394年）四月，李成桂為免除後患，遣中樞院副使鄭南晉、刑曹議郎咸傅霖絞死恭讓王及其二子。分遣刑曹典書尹邦慶、大將軍吳蒙乙至江華，刑曹典書孫興宗、僉節制沈孝生至巨濟，將囚禁在兩處的高麗宗室全部誅滅。結果，高麗宗室為躲避殺身之禍，將「王」氏增加筆畫，改為玉、全、琴、申、田、車、周、馬，以及龍、乃、金等姓氏，所以目前朝鮮半島的王姓人口十分稀少，成為稀姓。

更名朝鮮

洪武二十五年（1392年）七月，李成桂遣知密直司事趙胖至明朝禮部上表：「定昌府院君瑤權署國事，及今四年。瑤又昏迷不法，疏斥忠正，暱比讒邪，變亂是非，謀陷勛舊，諂惑佛神，妄興土木，靡費無度，民不堪苦；子奭癡佁無知，縱于酒色，聚會群小，謀害忠直。又其臣鄭夢周等潛成奸計，欲生亂階，乃將勛臣李成桂、趙浚、鄭道傳、南訚等譖于權署國事，令有司論劾以致謀害，國人憤怨，共誅夢周。權署國事尚不悛改，又謀殺戮。舉國臣民實慮社稷生靈俱被其害，惶懼失措，無可奈何，咸以為若所為難以主斯民奉社稷。洪武二十五年七月十二日，以恭愍王妃安氏之命，退居私第。竊念軍國之務不可一日無統，擇于宗親，無有可當輿望者，惟門下侍中李成桂澤被生靈，功在社稷，中外之心夙皆歸附。于是一國大小臣僚、閒良、耆老、軍民臣等咸願推戴，令知密直司事趙胖，前赴朝廷奏達，伏啟照驗，煩為聞奏，俯從輿意，以安一國之民。」禮部以明太祖聖旨答覆：「三韓臣民既尊李氏，民無兵禍，人各樂天之樂，乃帝命也。雖然，自今以後慎守封疆，毋生譎詐，福愈增焉。爾禮部以示朕意。」李成桂遣門下侍郎贊成事鄭道傳赴京謝恩，並獻馬六十匹。

當年八月，又遣前密直使趙琳赴京進表：「權知高麗國事臣李成桂言：伏惟小邦自恭愍王無嗣薨逝之後，辛旽子禑冒姓竊位者十有五年矣。迄至戊辰春，妄興師旅，將犯遼東，以臣為都統使，率兵至鴨綠江。臣竊自念小邦不可以犯上國之境，諭諸將以大義，即與還師，禑乃自知其罪，遜位子昌。昌亦暗弱，難以蒞位，國人啟奉恭愍王妃安氏之命，以定昌府院君王瑤權署國事。瑤乃昏迷不法，紊亂刑政，狎暱讒佞，貶斥忠良，臣民憤怨，無所控告。恭愍王妃安氏深慮其然，命歸私邸。于是一國大小臣僚、閒良、耆老、軍民等以為軍國之務不可一日無統，推戴臣權知軍國事。臣素無才德，辭至再三，而迫于眾情，未獲逃避，驚惶戰慄，不知所措。伏望皇帝陛下以乾坤之量、日月之明，察眾志之不可違、微臣之不獲已，裁自聖心，以定民志。」禮部再以明太祖旨意答覆：「高麗限山隔海，天造東夷，非我中國所治。爾禮部回文書，聲教自由，果能順天意合人心，以妥東夷之民，不生邊釁，則使命往來，實彼國之福也。文書到日，國更何號，星馳來報。」

當年十一月，再遣藝文館學士韓尚質至明朝上表：「竊念小邦王氏之裔瑤，昏迷不道，自底于亡，一國臣民推戴臣權監國事。驚惶戰慄，措躬無地間，欽蒙聖慈許臣權知國事，仍問國號，臣與國人感喜尤切。臣竊思惟，有國立號誠非小臣所敢擅便。謹將「朝鮮」（箕子所建古國名）、「和寧」（李成桂誕生之地）等號聞達天聰，伏望取自聖裁。」禮部複以明太祖旨意答覆：「東夷之號，惟朝鮮之稱美，且其來遠，可以本其名而祖之。體天牧民，永昌後嗣。」李成桂遣門下侍郎贊成事崔永沚謝恩，又遣政堂文學李恬送明朝頒賜的給前朝的高麗國王之印，並請更己名為李旦。

洪武二十八年（1395年）十一月，遣藝文春秋館太學士鄭總赴京請誥命印章：「洪武二十五年七月十五日，差知密直司事趙胖奏達天庭，繼差門下評理趙琳奉表陳奏，欽奉聖旨，許允權知國事。准奉禮部來咨內云：『國更何號，星馳來報。准此。』即差知密直司事韓尚質齎擎奏本赴京，欽奉聖旨節該：『東夷之號，惟朝鮮之稱美，且其來遠矣，可以本其名而祖之。欽此。』除欽遵外，洪武二十六年三月初九日，差門下評理李恬送納前朝高麗國王金印，又于當年十二月初八日准奉左軍都督督府咨，欽奉聖旨內一款節該：『即合正名。今既改號朝鮮，表文仍稱權知國事，未審何謀？欽此。』一國臣民戰慄惶懼，咸請國王欽遵施行。見今雖稱國王名號，竊緣未蒙頒降誥命及朝鮮國印信，一國臣民日夜顒望，仰天籲呼。伏請照驗，煩為聞奏，乞賜頒降國王誥命及朝鮮印信施行。」禮部以明太祖旨意拒絕：「今朝鮮在當王之國，性相好而來王，頑囂狡詐，聽其自然，其來文關請印信誥命，未可輕與。朝鮮限山隔海，天造地設，東夷之邦也，風殊俗異。朕若賜與印信誥命，令彼臣妾，鬼神監見，無乃貪之甚歟？較之上古聖人，約束一節決不可為。朕數年前曾敕彼儀從本俗，法守舊章，令聽其自為聲教。喜則來王，怒則絕行，亦聽其自然。爾禮部移文李成桂，使知朕意。」

李成桂由于一直沒有得到明太祖的冊封，在上書明朝時仍然使用「權知高麗國事」，國號更改後則使用「權知朝鮮國事」。朝鮮史官對李成桂屢上書明朝的事件，謂之「我太祖有百折不撓之毅」。

政治舉措

同年十一月，李成桂頒詔定都漢陽，建宗廟社稷、宮室城池。通過招撫、武力征服朝鮮半島東北地區的女真部落，李成桂令進一步加強了對該地區的管轄，使其疆域達到圖們江。同時由鄭道傳等人制訂了《經國大典》。鑑於明太祖批評高麗王室高麗諸王崇拜佛教而影響國事，李成桂推行崇儒抑佛的國策。寺院土地多被沒收，貴族莊園裡的奴婢都被釋放，並且實行開墾農地與改良農具谷種等勸農政策。

定都爭議

李成桂即位後，認為開京王氣已盡，開始積極謀劃遷都。即位後一個月就下旨由開京遷都漢陽（今韓國首爾，1395年改稱漢城），建宗廟社稷、宮室城池，並在1394年開始營建景福宮。其間，一個傳說相當傳神地刻畫了當年圍繞新都爭論的激烈情形——李成桂的摯友、高僧無學大師曾對漢陽的城池布局提出意見：「以仁王山作鎮，白岳南山為龍虎。」首席謀臣鄭道傳則以儒家立場反對怪力亂神之說：「自古帝王皆南面而治，未聞東向也。」二人互不相讓，場面劍拔弩張。最後，李成桂採納了鄭道傳的意見，無學挖苦鄭道傳：「不從吾言，垂二百年當思吾言。新羅義湘大師云：擇都漢陽，鄭姓人是非之，不過五世，篡奪之禍生；歲才二百，板蕩之難至。」1396年，在宗社宮闕營建完成以後，朝鮮正式定都漢城。李成桂即位後，對內繼續依靠鄭道傳等人實行改革，規劃新王朝的藍圖，對外則通過招撫、武力征服朝鮮半島東北地區的女真部落，李成桂令進一步加強了對該地區的管轄，使其疆域達到圖們江。

北拓

1384年，明派女真千戶白把山率70餘騎至北青州，意欲接管故元合蘭府轄區，由于兵力單薄，被高麗軍擊退。1388年明準備在元朝的雙城總管府地區立鐵嶺衛的舉動，促進了高麗加快向東北面發展的步伐。高麗表面對明朝「事大以誠」，暗地進一步向女真地區擴展勢力。1390年，高麗越過伊板嶺（摩天嶺）于海洋設吉州萬戶府。翌年七月，派李必等「齎榜文招諭東女真地面諸部落」。李成桂繼承了高麗的北拓，到1392年即王位後，元朝合蘭府轄區內的女真人，已大都附于朝鮮。如哈蘭（今咸鏡南道咸興）都達魯花赤奚灘訶郎哈，三散（今咸鏡南道北青）猛安古論豆蘭帖木兒，海洋（今咸鏡北道吉州）猛安括兒牙火失帖木兒，甲州（今兩江道甲山）猛安雲剛括，洪肯（今咸鏡南道洪原）猛安括兒牙兀難，禿魯兀（今咸鏡南道端川）猛安夾溫不花，斡合（今咸鏡北道鏡城）猛安奚灘薛列，阿沙（利城）猛家朱胡引答忽等部，均受招撫。《朝鮮王朝實錄》頌揚李成桂：「自孔州迤北至于甲山，設邑置鎮，以治民事，以練士卒」，「延袤千里，皆入版籍，以豆滿江為界。」

晚年生涯

第一次王子之亂

朝鮮太祖元年（1392年）八月，即位尚未逾月的朝鮮國王李成桂立繼室康氏為顯妃（元配韓氏在朝鮮開國前病死，贈節妃），封長子李芳雨鎮安君、次子李芳果永安君、三子李芳毅益安君、四子李芳幹懷安君、五子李芳遠靖安君（六子李芳衍早卒）、七子李芳蕃撫安君、駙馬興安君，以李芳果、李芳蕃、李濟為義興親軍衛節制使；同月，立八子李芳碩為世子。這次棄長立幼，引發了七年後的「戊寅靖社」。

太祖八年（1398年）八月，朝鮮國王李成桂久病不愈，靖安君李芳遠決定先下手為強，在李成桂庶弟義安君李和的支持下，以「立嫡以長」為藉口，聯合益安君李芳毅、懷安君李芳幹、上黨君駙馬李伯卿，殺死世子李芳碩，三軍府左軍節制使撫安君李芳蕃（李芳碩同母兄），三軍府右軍節制使興安君李濟（李芳碩同母姊婿），以及擁護世子李芳碩的大臣判三司事兼判三軍府事奉化伯鄭道傳、參贊門下府事兼判尚瑞寺事三軍節制使宜城君南訚、判中樞院事、同知中樞院事福城君。深受李成桂信任重用的世子一黨，已經被掃地殆盡。

李成桂在痛失愛子的慘境下，被迫承認既成事實，下教冊立李芳果為世子（長子李芳雨早逝）：「立嫡以長，萬世之經；宗子維城，寡人之望。惟爾父身嘗開國，舍長立幼，乃以芳碩為世子；不獨予暱愛不明之過，道傳、訚等亦不得辭其責矣。當其時，若以楚國愛少之誡據經廷諍，予敢不從？如道傳輩不惟不諍，猶恐其不立。日者，道傳、訚、孝生、至和等潛圖不軌，搖動根本，幸賴天地宗社之佑，罪人伏誅，王室再安。芳碩禍胎，不可留置國都，放諸東裔。予既悔前日之過，又因百僚之請，庸建爾為為王世子。于戲！克明其德，無忝爾所生；往盡乃心，鎮撫我社稷。」

九月五日，李成桂下傳位：「王若曰：余以否德，承祖宗之蔭，奉天子之靈，肇造邦家，撫有臣庶，于今七年。乃緣久于軍旅，蒙犯霜露，迨今年衰疾作，難于宵旰，庶務業劇，恐多遺失。惟爾王世子芳果，身居嫡長，夙著仁孝，且當開國之初贊襄弘多，一國臣民咸共知之。肆于洪武三十一年九月初五日告于宗廟，乃命以位。爾其率由典章，親君子遠小人，視聽無一己之偏，好惡公國人之論，無敢或荒，無敢或怠，永綏厥位，以昌後嗣。于戲！爾父薄德，雖不足效，先聖之道，布在方冊，夙興夜寐，爾尚敬哉！」世子李芳果即位，是為朝鮮定宗。

第二次王子之亂

「第一次王子之亂」之後，益安公李芳毅為中軍節制使，懷安公李芳幹為左軍節制使，靖安公李芳遠為右軍節制使；義安公李和判門下府事兼領義興三軍府事。懷安公李芳幹和靖安公李芳遠都擁有極大的勢力，並且都對王位虎視眈眈。

朝鮮定宗二年（1400年）正月，靖社功臣因為居功自傲，被朝鮮定宗免去商議中樞院事，心懷不滿，不斷挑起懷安公李芳幹與靖安公不和。李芳幹于是起兵攻擊李芳遠，兩軍在開城對戰，李芳幹兵敗被擒，被李芳遠流放，樸苞先被流放而後被殺。益安公李芳毅聽說兩人相鬥的事情後，痛哭流涕，即日交還兵權。李芳遠迅速清除了李芳幹的勢力。

同年二月，朝鮮定宗以沒有嫡子為由，下教冊立李芳遠為王世弟：「王若曰：建儲貳，所以正國本；崇位號，所以定人心。茲遵典章，庸舉冊禮。惟爾靖安公李芳遠，資全文武，德備英明。當太上開國之初，克倡大義；及寡兄定社之日，特立膚功。矧謳歌之有歸，宜監撫之是任。用命爾為王世子。于戲！知人不易，為子亦難。以親以賢，既處承祧之位；惟忠惟孝，用裨為政之方。故茲教示，想宜知悉。」當年四月，朝鮮國王李芳果與世子李芳遠採納司憲府兼大司憲權近、門下府左散騎金若採的建議，廢除自高麗王朝傳承下來的，禁止宗室、駙馬掌握私兵；五月，又命令朝鮮宗室、駙馬不再參與朝政。這樣，朝鮮王朝初期由于王子、駙馬掌握兵權、參與朝政引發的動亂，在制度上畫下了句號，朝鮮政局開始穩定下來。

定宗二年十一月，定宗李曔(李芳果登基後易此名)傳位李芳遠：「我神武太上王之肇興也，王世子明炳幾先，灼知天命，首唱大義，以建鴻業，則我朝鮮開國，惟世子之功是多，故當初建儲之議，物望咸歸。不期權奸貪立幼孽，將傾宗社，天誘其衷，建策戡定，以安宗社，則我朝鮮之再造，亦惟世子之功是賴。國于爾時，已為世子之有，乃執衝謙，申啟太上王，謂予不穀居嫡之長，俾命以位。予辭不獲，黽勉即政，于茲三年，天意未允，人心未孚，蝗旱為災，妖孽薦至。良由寡昧非德之致，慄慄危懼，俯仰有怍，矧予素纏風疾，眩于萬機，勞神應務，恐致彌留思釋重負以付有德，庶可以上答天心，下慰輿望。王世子稟剛明之德，挺勇智之資，仁義秉乎生知，孝悌本乎至誠，學問精于義理，英謀合于變通。固睿哲之離倫，乃謙恭之彌謹。早以濟世安民之量，克成撥亂反正之功。謳歌之所歸，宗社之所賴。惟賢惟德，宜承大統，爰命世子，傳即王位。予將退歸私第，優遊怡養，以保期頤。于戲！天人之情，必付于有德；宗社之統，當傳于至親。故世及以相承，實古今之通義。咨爾宗親耆老大小臣僚，咸體予懷，永保惟新之治。」世子李芳遠即位，是為朝鮮太宗。

第二次王子之亂後，李成桂的親信平壤伯趙浚、三司左僕射等人先後被下獄或流放。李成桂在神岩寺設法事追薦死于第一次王子之亂的李芳碩、李濟等人時，主事僧人也「暴死」。李成桂不悅，藉口「巡幸新都（漢城）」，于定宗二年十月十五日四更時帶著驛馬一百三十匹，從開京出奔。世子李芳遠追至碧蹄館，不果而返。後來李成桂在定宗的勸說下返回開城。

咸興差使

太宗李芳遠即位後，李成桂多次前往漢城、寶蓋山、平州溫泉等地巡幸。太宗元年閏三月十一日，李成桂藉口遊覽金剛山而再次離開開城，隨後前往安邊府，準備前往咸興，但在四月二十六日又返回開城，住在德壽宮中。同年八月，李成桂欲以「遊覽金剛山」的名義再次出京，被李芳遠以「朝廷（明朝）使臣即將來我國」為由阻止。十一月十七日，李成桂遣太監招李芳遠至德壽宮，與其回憶當年威化島回軍及「化家為國」之事。李芳遠日暮時回宮，李成桂欲當晚逃離開城，但因李芳遠在夜間再度拜謁而被阻止。十一月二十六日，李成桂藉口「巡幸逍遙山」，逃出開城，此後一直居住在逍遙山佛寺旁的宮殿中。

太宗二年十月，明朝使臣前往朝鮮，通報建文帝自焚、燕王登基之事。當時李成桂正在檜岩寺，遂與兩位明朝使臣溫全、楊寧一同游賞冬季的金剛山。十月二十七日，李成桂在澄波渡宴別溫全之後，率領侍衛前往東北面。李芳遠派樸錫命請李成桂返回開城，與明朝副使見面，李成桂回答說「使臣來則見之，不必王見也」。李芳遠不知李成桂去往何處，派遣使者探問，相望于道。李成桂對派來的使者說：「我從即位以來，沒有拜過祖宗之陵。如今幸好有空閒，所以先往東北面拜陵，然後遊覽金剛山，隨後還京，之後就不出門了。」十一月九日，李成桂御騎抵達咸興。

李成桂抵達咸興後，下令在鐵嶺關設兵阻攔一切人等出關，同時調集東北面安邊府、文州的兵馬。李芳遠為了探問李成桂的動向，多次派出「問安使」，但宋琉等使者被李成桂在咸興城牆上持弓射死，使者金玉謙則被捆縛手腳，以十餘人看守，後來趁守者熟睡而逃出。李芳遠一邊派無學大師勸說太上王回京，一邊任命左軍總制李龜鐵為東北面都體察使，大護軍韓興寶為東北面知兵馬使，並賜其御馬、弓矢、甲冑。

太宗二年十一月十三日，東北面都體察使李龜鐵、東北面都統使趙茂英、安州道都節制使、東北面江原道都安撫使金英烈等人率兵離開開城，前往咸興，李龜鐵被提升為中軍都總制。不久之後，李芳遠又下令釋放李成桂敬信的益倫、雪悟兩名僧人，令其隨安平府院君前往咸興。上護軍金繼志在鐵嶺關斬殺兩名守將，並殺死為李成桂兵馬運送糧草的金乙寶。十一月十七日，李芳遠又命、辛克禮二人率增援兵力前往東北面。十一月十八日，李成桂帶領親軍逃往西北面的孟州，當時李天祐正率領百餘游騎在孟州地區活動，被李成桂的親信截獲，李天祐與其子率十餘騎，力戰突圍。

十一月二十一日，李芳遠率領羽林軍離開京城，準備親征李成桂，命、、等人留守京城，金英烈、辛克禮守衛鐵嶺關。十一月二十五日，李芳遠任命為左道都統使，李叔蕃為都鎮撫使，閔無疾為都兵馬使，李至、郭忠輔、李行、韓珪等人為助戰節制使，領兵四萬餘人，向西北面進軍。十一月二十七日，趙思義的部隊在安州夜潰，第二天李成桂遣人通知李芳遠，稱自己準備迴鑾京城。

十二月八日，李成桂一行抵達金郊驛，李芳遠準備親自迎接，但其身邊的謀士特意提醒「殿下不宜接近太上王」，結果李芳遠前來朝拜之時，李成桂居然朝李芳遠放箭，箭射中帳殿的木樑，箭簇入木三分。李芳遠聲淚俱下，而李成桂則拋下裝有玉璽的匣子，大聲呵斥之後揚長而去。

此後李成桂被幽禁于開城的德壽宮中，後遷往漢城的昌德宮。由于安邊大都護趙思義、永興府尹金綣等官員曾隨李成桂起兵，因此安邊大都護府被降級為監務，永興府的長官從府尹被降格為知府。趙思義、金綣、金溫、裴尚忠、康顯、趙洪、洪洵、金子良、樸陽、李自芬、金昇、林西筠、文眾僉、韓定等與李成桂出奔有關的官員均被處決。

太宗八年（1408年）五月二十四日，李成桂崩逝于昌德宮廣延樓下別殿。共計在王位七年，在上王位十年，享壽七十三歲。明朝賜謚康獻。葬在漢城近郊楊州儉岩山下的健元陵。

尊號與諡號

洪武三十一年（太祖七年，1398年），李成桂被迫禪位，被尊為太上王。建文二年（定宗二年，1400年）六月，加尊號為「啟運神武太上王」。

永樂六年（太宗八年，1408年），李成桂去世，諡至仁啓運聖文神武大王，廟號太祖，明朝賜諡康獻，合稱康獻至仁啓運聖文神武大王，朝鮮史籍多稱為康獻大王和太祖大王。

康熙二十二年（肅宗九年，1683年），肅宗認為李成桂諡號中只有「聖文神武」四字算是諡號，「至仁啟運」則是尊號，所以加諡「正義光德」四字，為康獻至仁啓運聖文神武正義光德大王。

同治十年（高宗八年，1871年），高宗加尊號「應天肇統廣勳永命」八字，為康獻至仁啓運應天肇統廣勳永命聖文神武正義光德大王。

光武三年（1899年），高宗追尊李成桂為皇帝，改諡為至仁啓運應天肇統廣勳永命聖文神武正義光德高皇帝，廟號仍為太祖。

朝政

宰輔

• 左政丞趙浚

• 右政丞金士衡

• 門下侍中、南乙蕃、李崇、成汝完、李茂芳、偰長壽、鄭道傳、權僖、尹桓。

家庭

兄弟

• ：李成桂庶兄，母李氏。官至高麗同知密直，封完山君，死于朝鮮開國之前。朝鮮高宗九（1872）年十二月，追封完豐君。

• 義安大君李和：李成桂庶弟，母定嬪金氏。官至朝鮮判門下事兼判三軍府事，封義安君。

• 青海君李之蘭：李成桂義弟，女真千戶，原名豆蘭帖木兒。官至朝鮮門下贊成事，封青海君，謚「襄烈」。列名「三功臣」（開國、定社、佐命），青海李氏之始祖。

王后

• 承仁順聖神懿王后韓氏（1337年－1391年，54歲），本貫安邊，高麗密直司副使，安川府院君韓卿之女，祖父韓珪仁，外祖申元麗。至元三年（高麗忠肅王後三年，1337年）生。洪武二十四年（高麗恭讓王三年，1391年）去世，終年五十四。葬開城豐德齊陵。高宗追上尊號神懿高皇后。

• 順元顯敬神德王后康氏（1356年－1396年，40歲），本貫谷山，高麗判三司事，象山府院君康允成之女。洪武二十九年（太祖五年，1396年）八月十三日死於移御所。初草殮于漢城皇華坊，太宗二年改葬貞陵（在今首爾市內貞洞）。高宗追上尊號神德高皇后。

後宮

子女

子

（因神德王后被扶正為繼室，李成桂眾子皆為嫡出）

嫡女

庶女

相關影視作品及飾演者

• 《開國》：1983年KBS電視劇， 飾。

• 《朝鮮王朝五百年》—《》：1983年MBC電視劇， 飾。

• 《龍之淚》：1996年KBS電視劇， 飾。

• 《辛旽》：2005年MBC電視劇， 飾。

• 《大風水》：2012年SBS電視劇，池珍熙 飾。

• 《鄭道傳》：2014年KBS電視劇，劉東根 飾。

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