The Lost Empire Balhae: Finding Its True Owner Amid Northeast Project Controversies

A journey to find the true owner of Balhae, the empire that vanished a thousand years ago amid the harsh winds of the Manchurian plains.

• Understand the core logic behind the Northeast Project’s claim that Balhae is part of Chinese history.
• Examine clear evidence proving Balhae was a Korean nation that succeeded Goguryeo.
• Grasp why ancient history debates remain crucial to us today.

Imagine standing against the harsh winds of the Manchurian plains. Before you lie only faint outlines of a city that was once the heart of a great empire. This is the former site of Balhae, a vanished empire like a ghost. And one question arises: Who truly owns the history buried beneath this land?

This empire, which ruled East Asia for 228 years, now stands at the center of the fiercest “history war” of the 21st century: China’s Northeast Project (Dongbuk Gongjeong, 东北工程). This is not merely a debate about the past but an ongoing battle tied to national identity and future.

This article embarks on a journey into the heart of this grand conflict, following clues left by the Balhae people to hear their voices directly.

Part 1: The Phoenix of Goguryeo – The Birth and Flourishing of Balhae

A kingdom rising from ashes

The story begins in 668 AD with the tragic fall of the mighty Goguryeo Empire. Among the scattered refugees was a man destined to become a key figure in history: Dae Joyeong (大祚榮), a former Goguryeo general. He carried the hope of a fallen nation.

In 696, when the Khitan rebelled and the Tang dynasty’s northeastern border was thrown into chaos, Dae Joyeong seized the opportunity. Leading Goguryeo refugees and allied Malgal tribes, he made a desperate escape and won a miraculous victory against Tang forces at the Battle of Tianmenling.

Finally, in 698, he established a new kingdom called Jin (振) at the foot of Dongmo Mountain, boldly announcing their revival to the world.

“A flourishing country east of the sea” (海東盛國)

Balhae grew into an empire encompassing Manchuria, northern Korea, and Primorsky Krai. Standing shoulder to shoulder with Silla in the south and guarding the north, it was the true successor of Goguryeo. Later, the Silhak scholar Yu Deukgong named this period the “Northern and Southern States Era (南北國時代)”.

Under the 10th ruler, King Seon, Balhae reached its zenith. Even the Tang dynasty envied it, bestowing the nickname “Haedong Seongguk (海東盛國)”, meaning “a flourishing country east of the sea”.

However, in 926, a sudden surprise attack by the rising Khitan led to the empire’s collapse. Balhae left behind a brilliant legacy and a vast historical void, which became the opening act of today’s “owner-finding” war.

Part 2: The Claim of a ‘Chinese Local Regime’ – Dissecting the Northeast Project’s Logic

How does the Northeast Project define Balhae? Their core claim is that Balhae was not a Korean nation but a local regime established by the Malgal tribe under the Tang dynasty.

• Logic 1: The founder was Malgal Chinese academia cites the Old Book of Tang (旧唐书) phrase stating “Dae Joyeong was originally a branch of Goguryeo, from the Sumo Malgal tribe (本高麗別種粟末靺鞨)” to argue his lineage was Malgal. Since Malgal are a Chinese minority today, Balhae naturally becomes part of Chinese history.
• Logic 2: The name and kingship were granted by Tang They argue that because the Tang dynasty bestowed the title “King of Balhae Commandery (渤海郡王)” on Dae Joyeong in 713, Balhae’s identity was subordinate and dependent on Tang.
• Logic 3: Tribute and investiture prove a hierarchical relationship Balhae’s tribute to and investiture by Tang are presented as clear evidence of a lord-vassal relationship, concluding Balhae was merely a “local regime” within the Tang empire.

These claims stem not from pure academic curiosity but from a political necessity to emphasize a “unified multiethnic state theory (统一的多民族国家论)”. By incorporating all history within current Chinese borders into Chinese history, China aims to block separatist movements of minorities and prevent future territorial disputes.

Part 3: The Echo of Goguryeo – Evidence of a Korean Nation

Now, it’s time to put on the detective’s lens and find evidence to refute the Northeast Project’s claims. Fortunately, the Balhae people left their true story scattered everywhere.

Clue 1: Diplomatic documents testify – “We are kings of Goguryeo”

The most devastating evidence against the “local regime” claim is Balhae’s own voice. In official diplomatic letters sent to Japan, known as state letters (國書), they clearly declared their identity.

• In 727, King Mu proudly declared in a letter to Japan that they had “restored the old lands of Goguryeo (復高麗之舊居)”.
• His successor, King Mun, called himself “King Daehinmu of Goguryeo (高麗國王 大欽茂)”, where “Goryeo” refers to Goguryeo.

This is corroborated by Japan’s official historical record, the Shoku Nihongi (續日本紀), which consistently refers to Balhae as “Goryeo” and its envoys as “Goryeo emissaries (高麗使)”. A “local regime” could never form an alliance with another country (Japan) against its suzerain (Silla under Tang).

Clue 2: The truth beneath the ground – The two princesses and the ondol story

One of the most fascinating parts is archaeological evidence. Like a time capsule left by Balhae, artifacts and ruins do not lie.

• Tombs of Princess Jeonghye and Princess Jeonghyo: The graves of King Mun’s two daughters provide decisive clues. Princess Jeonghye’s tomb is a typical Goguryeo-style stone chamber tomb. Her younger sister’s tomb, influenced by Tang brick tombs, still retains the Goguryeo traditional wooden beam ceiling structure. Crucially, the epitaph refers to their father King Mun with the imperial title “Hwangsang (皇上)”, used only for emperors.
• Traces of Ondol (underfloor heating): Ondol, a unique Korean heating system, is found throughout Balhae’s capital, noble and commoner residences, and even across the vast territory reaching Russia’s Primorsky Krai. This shows direct cultural continuity from Goguryeo.

These prove Balhae did not passively adopt Tang culture but confidently selected foreign elements while proudly inheriting Goguryeo’s legacy as an independent empire.

Clue 3: The power of names – Use of independent era names

Balhae used its own era names (年號) such as In-an (仁安) and Daeheung (大興). In East Asian worldview, proclaiming an independent era name was the ultimate expression of sovereignty, reserved only for the “Son of Heaven” (emperor). This alone fundamentally shakes the “local regime” theory.

Clue 4: War cries for independence

In 732, King Mu launched a naval preemptive strike against Dengzhou (Shandong Peninsula) of Tang to check its power. This was a clear act of international war by a sovereign state defending its interests. A “local regime” would never attack its central government across the sea.

Part 4: External Voices – How the International Community Views Balhae

What do third-party witnesses say about Balhae?

• Northern perspective (Russia): Early Russian scholars relied on Chinese sources, but since the 1990s, archaeological finds like ondol in Primorsky Krai have shifted views. Many Russian scholars now conclude Balhae was an independent state succeeding Goguryeo.
• Eastern perspective (Japan): Ancient Japan, as a direct witness to Balhae, recorded it vividly as an independent state succeeding Goguryeo. However, some modern Japanese scholars downplay this, preferring the neutral term “multiethnic state.” When seeking historical truth, shouldn’t we give more weight to contemporary eyewitness testimony than modern reinterpretations?

Conclusion

All evidence points to one conclusion: Balhae was never a passive local regime of China. It was a proud, independent, and powerful northern Korean empire succeeding Goguryeo.

This struggle matters because it is not confined to the past. The logic of the Northeast Project extends today into the “Cultural Project (文化工程)”, which claims kimchi, hanbok, and other Korean cultural elements as Chinese. It is the same logic of absorbing neighboring cultures under the vast umbrella of “Zhonghua (中華)”.

• Key Summary

1. Balhae explicitly declared itself the successor of Goguryeo.
2. Archaeological evidence like tombs and ondol proves direct cultural succession from Goguryeo.
3. The Balhae historical debate is part of an ongoing cultural war involving kimchi, hanbok, and more.

The fight to preserve Balhae’s history is ultimately a fight to protect our right to tell our own story. Listening to the questions posed by this ghost empire on the Manchurian plains is our duty today.