Flags of South Korea

Republic of Korea (South Korea)

Who & why: the Republic of Korea is proclaimed on 15 August 1948 in the American-occupied south, with Syngman Rhee as its first president, formalizing the division that followed Japan's 1945 defeat. North Korean forces invade the south in June 1950, starting the Korean War; UN and mainly American forces intervene, Chinese forces enter on the North's side, and the 1953 armistice (never replaced by a formal peace treaty) leaves the peninsula divided along a heavily fortified line near the original 38th parallel. South Korea moves from decades of authoritarian rule under successive military-linked presidents to full multi-party democracy by the late 1980s, and grows into one of the world's largest economies.

What it represents: the Taegukgi, first adopted in 1883 under the late Joseon Dynasty and carried forward essentially unchanged: a red-and-blue taegeuk (yin-yang) circle for cosmic balance, surrounded by four trigrams (geon, gon, gam, ri) representing heaven, earth, water, and fire, on a white field standing for peace and purity.

US Army Military Government in Korea (south of the 38th parallel)

Who & why: Japan's August 1945 surrender ends its colonial rule over Korea; the United States and the Soviet Union, acting on a hastily drawn wartime plan, divide the peninsula for occupation purposes along the 38th parallel, with American forces administering the south. Efforts at a unified Korean trusteeship collapse amid Cold War tension, and the US administration oversees the transition to the separate Republic of Korea, proclaimed in the south in August 1948.

What it represents: the traditional Taegukgi, already a symbol of Korean national identity since the late Joseon period, flies unofficially as a mark of Korean identity even before the new republic's formal 1948 adoption confirms it as the national flag.

Japanese colonial rule (Korea under Japan)

Who & why: after decades of growing Japanese influence following the 1876 opening of Korea and the 1905 protectorate treaty, Japan formally annexes Korea in August 1910, ending the Korean Empire's independence. Thirty-five years of colonial rule follow, including forced labor and cultural assimilation policy in the war years, stated here factually and without gratuitous detail; a major nonviolent independence movement, the March First Movement of 1919, is met with harsh suppression but leads to a Korean Provisional Government in exile. Colonial rule ends with Japan's surrender in August 1945.

What it represents: Japan's own Hinomaru (see this atlas's Japan page), flown as the flag of the colonizing power; the Taegukgi is banned from official use throughout this period but persists as an underground symbol of Korean national identity, including among the Provisional Government in exile.

Korean Empire

Who & why: King Gojong proclaims the Korean Empire in October 1897, elevating Joseon's status to formally match its neighbors' imperial titles and asserting full independence after centuries of a tributary relationship with China. The Korean Empire pursues cautious modernization reforms but cannot resist mounting Japanese pressure, becoming a protectorate in 1905 and being formally annexed in 1910.

What it represents: the same Taegukgi already adopted in 1883, now flown as the flag of a formally sovereign empire rather than a tributary kingdom.

Joseon Dynasty (Taegukgi adopted)

Who & why: as Joseon opens to Western and Japanese trade through the 1870s–80s, its diplomats need a national flag for the first time to conduct treaty relations under then-standard international practice; envoy Park Yeong-hyo is generally credited with formalizing the design, officially adopted in 1883, drawing on an older Joseon royal taegeuk emblem. Joseon at this point remains a nominal tributary of Qing China even as it modernizes, a relationship it formally ends with the 1897 proclamation of the Korean Empire.

What it represents: the taegeuk (yin-yang) circle representing cosmic balance and harmony, a symbol with a much older history in Korean art and philosophy, formalized here for the first time as a national flag; the four trigrams follow soon after as part of the same design tradition.

Joseon Dynasty (pre-flag era)

Who & why: General Yi Seong-gye founds the Joseon Dynasty in 1392, ruling Korea for over five centuries — one of the longest-lived dynasties anywhere in East Asia. Joseon adopts Confucianism as state ideology, creates the Hangul writing system under King Sejong in the 1440s, and survives major Japanese (1592–98) and Manchu (1636–37) invasions, while maintaining a tributary relationship with Ming and then Qing China throughout most of this span.

What it represents: no national flag is adopted until near the very end of this period (1883); royal authority instead uses Confucian court ritual, official seals, and Joseon's own associated color symbolism. Shown here with a dynastic blue reference rather than an invented banner.

Goryeo Dynasty

Who & why: Wang Geon founds Goryeo in 918 and completes the reunification of the Korean peninsula by 936, absorbing the last remnants of the fractured post-Silla period; the dynasty's own name is the direct source of the modern English word "Korea." Goryeo survives repeated Khitan invasions and, from the 1230s, devastating Mongol invasions that eventually force it into subordinate status within the Mongol Empire's sphere for roughly a century, before it is overthrown by its own general, Yi Seong-gye, founding Joseon in 1392.

What it represents: no state flag is documented in this period; Goryeo court and Buddhist symbolism (the dynasty is closely associated with state-sponsored Buddhism, including production of the Tripitaka Koreana) substitute for any flag.

Unified Silla

Who & why: Silla, allied with Tang China, defeats its rival kingdoms Baekje (660) and Goguryeo (668) and then expels its own former Tang allies, achieving the first political unification of most of the Korean peninsula by 676. Unified Silla presides over a golden age of Buddhist art and culture centered on its capital Gyeongju before weakening in its final decades, fragmenting into the brief Later Three Kingdoms period that Goryeo's founder reunifies by 936.

What it represents: no flag is documented for Silla; Buddhist iconography and royal Silla court symbolism take its place in the historical record.

Three Kingdoms of Korea (Goguryeo, Baekje, Silla)

Who & why: traditional founding dates place Goguryeo (in the north, extending into Manchuria), Baekje (southwest), and Silla (southeast) all emerging around the turn of the millennium, though reliable historical attestation for each strengthens over the following centuries; this page uses one honest bridging entry for this genuinely contested, multi-centered span rather than inventing false precision. The three kingdoms compete, ally, and fight one another and outside powers (including Tang China and Yamato Japan) for over seven centuries, before Silla's Tang-allied conquest of Baekje and then Goguryeo ends the period in 668, opening the way to unification.

What it represents: no flags survive from any of the three kingdoms; royal tombs, Buddhist temple art (introduced to each kingdom at different points), and court chronicles are the main surviving record of this era's own symbolism.

Gojoseon ("Old Joseon")

Who & why: Gojoseon is the earliest state Korean tradition and Chinese written sources agree existed on the peninsula and in southern Manchuria, though its exact founding date, extent, and institutions before its final centuries remain genuinely uncertain and are the subject of ongoing historical and archaeological debate; this page states that uncertainty plainly rather than asserting false precision. Its documented final phase ends in 108 BCE when Han China conquers it; the power vacuum and Chinese commanderies that follow set the stage for the Three Kingdoms era already covered on this page, with Goguryeo in particular emerging from former Gojoseon territory.

What it represents: no flag survives or is plausibly attested for Gojoseon in any modern sense; shown here honestly blank. Bronze daggers, dolmens, and later temple and chronicle art are the main surviving material record.

World context: Gojoseon's historically attested span runs alongside the Warring States period and Qin unification of China (221 BCE) with the first Great Wall construction, the Achaemenid Persian Empire and classical Greece, Alexander's conquests, and the rise of Rome from republic toward empire — placing Korea's earliest recorded state within the same centuries as the Mediterranean and East Asian civilizations most commonly taught alongside it.