Korea Through 5,000 Years — Episode 3

A History in Parallel with the West

When people in the West think of the early Middle Ages, they often imagine a world that emerged after the fall of Rome.

The Western Roman Empire was gone.

New kingdoms were forming across Europe.

The Byzantine Empire still ruled from Constantinople.

Islamic civilization was expanding across the Middle East, North Africa, and eventually into Spain.

Charlemagne would build a powerful empire in Western Europe.

And Viking ships would soon appear along the coasts of Britain and continental Europe.

But what was happening in Korea during the same centuries?

At the eastern end of Eurasia, the Korean Peninsula was also entering a new age.

The centuries-long struggle among Goguryeo, Baekje, and Silla had ended.

Silla controlled most of the Korean Peninsula.

To the north, however, a new kingdom called Balhae arose from the political world left behind by Goguryeo.

For more than two centuries, these two states existed side by side.

Silla in the south.

Balhae in the north.

This period is sometimes called Korea's North–South States Period.

It was an age of Buddhist art, international trade, great cities, expanding diplomatic networks, and cultural exchange across East Asia.

And it unfolded at the same time that Baghdad, Constantinople, Aachen, and the Viking world were shaping the future of the West.

1. Silla Wins the War — Then Faces Its Ally

In Episode 2, we saw the rise of Goguryeo, Baekje, Silla, and Gaya during the same centuries that Rome dominated the Mediterranean.

By the seventh century, the balance of power on the Korean Peninsula had changed dramatically.

Gaya had already been absorbed by Silla in 562.

But Goguryeo and Baekje remained formidable rivals.

Silla therefore turned to the most powerful state in East Asia:

Tang China.

The Silla–Tang alliance transformed the military situation.

In 660, allied Silla and Tang forces destroyed Baekje.

Eight years later, in 668, Goguryeo also fell.

At first glance, Silla seemed to have achieved its goal.

Its two greatest rivals were gone.

But there was a problem.

Tang China had not fought simply to create a stronger Silla.

The Tang government attempted to establish its own administrative control over the territories of the defeated kingdoms.

Silla suddenly discovered that its former ally had become a potential master.

The alliance became a war.

2. The Silla–Tang War

Silla now fought Tang forces for control of the Korean Peninsula.

This was a remarkable reversal.

Only a few years earlier, the two states had fought together against Baekje and Goguryeo.

Now Silla was trying to prevent the Tang Empire from dominating the peninsula.

The conflict continued through the 670s.

By 676, Silla had succeeded in pushing Tang forces northward and established control over most of the Korean Peninsula south of the Daedong River.

This date is conventionally used to mark the beginning of the Unified Silla period.

But the word “unified” needs explanation.

Silla did not control all of the former Goguryeo territories.

Large areas of Manchuria and the northern regions remained outside Silla's rule.

And within only a few decades, another powerful state would emerge there.

That state was Balhae.

By 676, Silla had driven Tang forces northward and secured control over most of the Korean Peninsula.

3. Meanwhile, a New State Rises in the North

The destruction of Goguryeo in 668 did not erase its people or political traditions.

Many former Goguryeo communities remained across Manchuria and northern Korea.

Others were displaced into Tang territory.

Several decades later, political instability created an opportunity.

In 698, Dae Joyeong established a new state in the northeast.

That state became known as Balhae.

Balhae drew upon people and traditions associated with the former Goguryeo world while also incorporating a large Mohe population and other groups of Northeast Asia.

This made Balhae a culturally and politically complex state.

Its territory eventually extended across large parts of Manchuria, the northern Korean Peninsula, and areas reaching toward today's Russian Far East.

Suddenly the political map of Korea and Northeast Asia looked very different.

The age of the Three Kingdoms had ended.

A new two-state structure had emerged:

Silla in the south.

Balhae in the north.

4. The North–South States Period

Korean historians often describe the centuries in which Silla and Balhae coexisted as the North–South States Period.

This term is useful because it corrects one misleading impression created by the expression “Unified Silla.”

Silla had indeed brought most of the Korean Peninsula under a single government for the first time.

But Korea's historical world did not end at the northern boundary of Silla.

Balhae occupied enormous territories associated with the former northern world of Goguryeo.

For more than two centuries:

Unified Silla — 676–935

and

Balhae — 698–926

existed simultaneously.

They interacted with one another.

They competed.

They maintained diplomatic relations.

And both participated in the international order centered on Tang China.

To understand Korea during the early Middle Ages, we therefore need to look at both states.

During the eighth and ninth centuries, Unified Silla and Balhae formed a north–south political order in Northeast Asia.

5. Gyeongju: One of East Asia's Great Cities

The capital of Silla was Gyeongju.

By the eighth century, it had become one of the great cities of East Asia.

Royal palaces, aristocratic residences, Buddhist temples, administrative buildings, markets, roads, and gardens filled the capital.

The city reflected the enormous wealth accumulated by the Silla monarchy and aristocracy.

But Gyeongju was not merely a Korean political center.

It was an international city.

Envoys, monks, merchants, scholars, and travelers moved between Silla and Tang China.

Connections extended to Japan.

Objects and cultural influences from farther west also reached the Korean Peninsula through the enormous exchange networks of Eurasia.

Luxury goods moved through Central Asia and China.

Religious ideas traveled with monks.

Artistic techniques crossed borders.

Foreign styles were adopted and transformed into distinctly Korean forms.

If a traveler had entered Gyeongju during its eighth-century peak, the city would not have appeared as an isolated settlement at the edge of the world.

It was part of a sophisticated international civilization.

6. Buddhism Reaches a Cultural Peak

Buddhism had entered Korea centuries earlier during the Three Kingdoms period.

Under Unified Silla, however, Buddhist culture reached extraordinary heights.

Royal families and aristocrats supported temples.

Monasteries became centers of learning.

Monks studied philosophy and traveled abroad.

Sculptors produced sophisticated images of Buddhas and bodhisattvas.

Architects built monumental religious complexes.

Two of the most famous achievements of this age are:

Bulguksa Temple

and

Seokguram Grotto.

Both are associated with Silla's eighth-century cultural flourishing.

Bulguksa represented an ideal Buddhist world expressed through architecture.

Seokguram transformed stone, sculpture, mathematics, architecture, and religious symbolism into one of the masterpieces of East Asian Buddhist art.

The seated Buddha inside Seokguram is surrounded by carefully arranged figures carved into stone.

It was not simply decoration.

The entire space was designed as a sacred cosmological environment.

7. While Byzantium Debated Images, Silla Created Buddhist Masterpieces

Here we find another fascinating East–West comparison.

During the eighth century, Silla was constructing and supporting magnificent Buddhist images and temples.

At roughly the same time, the Byzantine Empire was experiencing one of the most intense religious controversies in its history:

Iconoclasm.

Beginning in the eighth century, Byzantine rulers and religious leaders debated whether sacred images of Christ, Mary, and the saints should be venerated.

At various times, religious images were restricted or destroyed.

Supporters of icons resisted.

The conflict continued in phases for more than a century.

Meanwhile, thousands of kilometers away, Silla rulers and aristocrats were investing heavily in Buddhist visual culture.

Both societies took religious images extremely seriously.

But they were moving through very different debates about what sacred art meant.

This is exactly why parallel history is useful.

The same century can produce very different religious and artistic worlds.

8. Korea and the World's Early Printing Culture

One particularly remarkable object was discovered at Bulguksa.

During restoration work on the temple's Seokgatap pagoda in the twentieth century, scholars discovered a Buddhist text known as the Mugujeonggwang Daedaranigyeong, or Great Dharani Sutra of Immaculate and Pure Light.

The surviving printed material dates to the Unified Silla period and is associated with the early eighth century.

It is one of the earliest surviving examples of woodblock printing.

This was long before Gutenberg.

Of course, movable metal type belonged to a much later chapter of Korean history.

But the Silla example demonstrates that printing technology already formed part of East Asian Buddhist culture centuries before printing transformed early modern Europe.

Buddhist texts created a powerful demand for reproduction.

Printing could multiply sacred words.

Technology and religion therefore reinforced one another.

This relationship would become extremely important later in Korean history.

9. 751: Building Silla's Buddhist Golden Age

The year 751 is traditionally associated with major reconstruction projects at Bulguksa and the creation of Seokguram.

Place that date on the wider world timeline.

Korea

Silla was at or near the cultural height of its unified period.

Buddhist architecture and sculpture flourished.

Gyeongju was a prosperous capital.

Byzantine Empire

The empire was still engaged in the iconoclastic era.

Islamic World

The Abbasid Revolution had just transformed the Islamic political order.

Within a few years, a new city would emerge as one of the world's greatest centers of learning and commerce.

That city was:

Baghdad.

10. Baghdad and Gyeongju

In 762, the Abbasid caliph al-Mansur founded Baghdad.

The city would become the political and intellectual center of one of the most sophisticated civilizations of the medieval world.

Scholars, merchants, physicians, mathematicians, philosophers, and translators gathered there.

Trade routes connected Baghdad with Central Asia, India, Africa, and the Mediterranean.

Now consider the same period in Korea.

Gyeongju was flourishing under Unified Silla.

The two cities were separated by thousands of kilometers.

They belonged to different civilizations.

They spoke different languages.

They followed different religions.

But both were connected to larger systems of international commerce and cultural exchange.

Between them stretched Central Asia, Persia, the Silk Roads, Tang China, and numerous intermediary societies.

A merchant or object did not have to travel directly from Baghdad to Gyeongju for the two worlds to be indirectly connected.

Goods, technologies, artistic styles, and information could move step by step across Eurasia.

11. Balhae Becomes a Great Northern Kingdom

While Silla flourished in the south, Balhae was also expanding.

Its rulers built an organized administrative system and established several regional capitals.

The kingdom absorbed influences from Tang China while preserving political and cultural elements associated with Goguryeo and the diverse peoples of its northern territory.

Balhae's cities contained:

palaces,
Buddhist temples,
government buildings,
planned streets,
decorated roof tiles,
sculptures,
and sophisticated architecture.

Its territory was enormous compared with Silla's.

Balhae extended through much of today's northeastern China and into the Russian Maritime Province, as well as part of the northern Korean Peninsula.

By the ninth century, Balhae had become prosperous enough to receive a celebrated description in East Asian historical records.

It was praised as a flourishing state of the eastern sea.

Balhae was not simply a remote frontier kingdom.

It was one of the major states of Northeast Asia.

12. Silla and Balhae Were Not Isolated Rivals

Relations between Silla and Balhae were complicated.

They were political competitors.

Their historical origins were different.

Their diplomatic positions toward Tang China could differ.

But they were not permanently at war.

Both operated inside a broader East Asian diplomatic system.

Balhae sent missions to Tang China and Japan.

Silla maintained extensive relations with Tang and Japan as well.

Routes connected the states.

Diplomats traveled.

Merchants traveled.

Monks traveled.

Political information moved with them.

The Korean Peninsula and Manchuria were part of a highly connected regional world.

13. 793: Vikings Attack Lindisfarne

Now shift to the opposite side of Eurasia.

In 793, Viking raiders attacked the monastery of Lindisfarne off the coast of northern England.

The attack became one of the traditional markers for the beginning of the Viking Age.

Images of longships, warriors, raiding parties, and northern exploration would come to define this period of European history.

But what was happening in Korea at approximately the same time?

Around 793

Silla

Gyeongju remained one of East Asia's great Buddhist capitals.

Its elite culture had reached extraordinary sophistication.

Balhae

King Mun's long reign was ending.

Balhae had developed extensive diplomatic institutions and a complex state system.

Western Europe

The Viking Age was beginning.

Islamic World

Baghdad was becoming one of the world's great urban centers.

Byzantium

Religious and political conflicts surrounding sacred images continued.

Once again, the contrast is striking.

The phrase “early Middle Ages” describes very different realities depending on where we stand.

14. Charlemagne and the Korean States

Only seven years after the Lindisfarne raid came another famous moment.

800 CE.

On Christmas Day, Pope Leo III crowned Charlemagne emperor in Rome.

Charlemagne had united much of Western and Central Europe under his rule.

His empire helped shape the political development of medieval Europe.

He promoted administrative reforms, education, Christianity, and the cultural revival later known as the Carolingian Renaissance.

Now look east.

Around 800 CE, Unified Silla was still ruling most of the Korean Peninsula.

Balhae controlled a vast northern territory.

Tang China remained one of the world's great civilizations, although internal problems were increasing.

Japan was in the early Heian period after moving its capital to Heian-kyo—modern Kyoto—in 794.

So when Charlemagne was crowned emperor in Rome, East Asia contained its own complex network of kingdoms and empires.

The medieval world was not centered in one place.

There were many centers.

When Charlemagne was crowned emperor in 800 CE, Unified Silla and Balhae were flourishing at the opposite end of Eurasia.

15. Jang Bogo and Maritime Korea

The story of Unified Silla was not limited to palaces and temples.

The sea was becoming increasingly important.

One of the most famous figures of ninth-century Korea was Jang Bogo.

In 828, he established Cheonghaejin, a maritime base on Wando Island off Korea's southwestern coast.

From there, Jang Bogo built influence over maritime routes linking:

Korea

Tang China

and

Japan.

His activities demonstrate the importance of the sea in Korean history.

Trade was not simply continental.

Ships carried people, goods, messages, religious ideas, and commercial networks across East Asian waters.

Silla merchants and communities could also be found in parts of China.

The image of medieval Korea as isolated behind its mountains is therefore misleading.

Korea was connected both by land and by sea.

16. The Wider Eurasian World

By the ninth century, the world around Korea formed part of an enormous chain of civilizations.

To the west:

The Abbasid Caliphate connected the Middle East with Central Asia.

The Byzantine Empire continued the eastern Roman tradition.

The heirs of Charlemagne ruled parts of Western Europe.

The Vikings traveled from Scandinavia into Britain, Ireland, continental Europe, the rivers of Eastern Europe, and eventually even farther.

In Central Asia:

Turkic peoples, merchants, Buddhist communities, Muslims, Christians, and others interacted along complex trade routes.

Farther east:

Tang China remained a powerful cultural center.

Silla and Balhae participated in its diplomatic and commercial networks.

Japan was developing the Heian court culture.

The early medieval world was therefore not a collection of completely isolated civilizations.

It was a mosaic of interconnected regions.

The connections were slower and less direct than today.

But they were real.

17. Two Korean States, Two Different Geographies

Unified Silla and Balhae had very different geographic realities.

Unified Silla

Its territory was concentrated mainly on the Korean Peninsula.

Its heartland included fertile agricultural regions.

Its capital, Gyeongju, was a major political and cultural center.

Its maritime position helped connect it with China and Japan.

Balhae

Its territory extended across a much larger northern landmass.

Its environment included forests, mountains, plains, and long continental routes.

It bordered powerful northern peoples and Tang China.

Its rulers needed to govern populations spread across enormous distances.

These different geographies shaped different political systems and strategic priorities.

But both states belonged to the history of Korea and Northeast Asia.

18. The Beginning of Decline

Periods of prosperity do not last forever.

By the late ninth century, Silla was facing serious internal problems.

Powerful aristocratic families competed for influence.

The central monarchy weakened.

Regional military leaders became increasingly independent.

Heavy burdens on peasants contributed to unrest.

Rebellions spread.

The central government in Gyeongju found it increasingly difficult to control the countryside.

The political unity established after 676 was beginning to unravel.

New regional powers appeared.

By the beginning of the tenth century, Korea had entered what historians call the Later Three Kingdoms period.

The names of old kingdoms returned.

Later Baekje.

Later Goguryeo, later known as Taebong.

And the weakened kingdom of Silla.

History seemed to be repeating itself.

But a new state was about to emerge.

19. 918: The Birth of Goryeo

In 918, a military leader named Wang Geon established a new kingdom.

He called it:

Goryeo.

The name deliberately recalled Goguryeo.

It is from the name Goryeo that the modern English word Korea ultimately derives.

Wang Geon would eventually defeat his rivals and reunify most of the peninsula.

But that belongs to our next major chapter.

At the moment Goryeo appeared, another northern kingdom still existed.

Balhae.

20. 926: The Fall of Balhae

In the early tenth century, a new power was rising in Manchuria.

The Khitan.

In 926, Khitan forces conquered Balhae.

After more than two centuries, the northern kingdom disappeared.

Many Balhae people remained in the region.

Others moved south.

Some, including members of the Balhae ruling elite, entered Goryeo.

This was historically significant.

The newly established Goryeo kingdom accepted Balhae refugees and incorporated part of Balhae's historical legacy into its own political world.

Only nine years later, another ancient state would disappear.

21. 935: The End of Silla

In 935, the last king of Silla surrendered to Goryeo.

A kingdom traditionally founded in 57 BCE had finally come to an end.

Few dynasties anywhere in the ancient and medieval world could claim such longevity.

The royal capital of Gyeongju lost its position as the political center of Korea.

But Silla's cultural legacy remained enormous.

Buddhist art.

Temples.

Architecture.

Royal tombs.

Administrative traditions.

Literature.

Religious scholarship.

And the historical memory of a state that had brought much of the Korean Peninsula under one political system.

The political world of ancient Korea was ending.

The medieval kingdom of Goryeo was taking its place.

22. Korea and the West — A Parallel Timeline

Date	Korea	West / Wider World
660	Silla–Tang forces defeat Baekje	Early Islamic caliphates expand
668	Goguryeo falls	Byzantine Empire survives major regional upheaval
676	Silla drives Tang forces north; Unified Silla period begins	Early medieval kingdoms develop in Europe
698	Dae Joyeong establishes Balhae	Umayyad Caliphate dominates much of the Islamic world
711	Silla and Balhae coexist	Muslim forces enter the Iberian Peninsula
751	Silla Buddhist culture near its peak; Bulguksa and Seokguram era	Abbasid Revolution reshapes Islamic world
762	Gyeongju flourishes as an international capital	Baghdad is founded
793	Silla and Balhae flourish	Viking raid on Lindisfarne
800	North–South States period	Charlemagne crowned emperor in Rome
828	Jang Bogo establishes Cheonghaejin	Viking Age expands across Europe
9th century	Balhae reaches a period of great prosperity	Abbasid, Byzantine and Carolingian worlds coexist
918	Wang Geon establishes Goryeo	Post-Carolingian Europe
926	Balhae falls to the Khitan	Viking Age continues
935	Silla submits to Goryeo	Medieval European kingdoms consolidate

23. Was This Really a Korean “Middle Ages”?

The term Middle Ages was originally created to describe European history.

It refers to the period between classical antiquity and the early modern world.

Applying the term directly to Korea can therefore be misleading.

Korea did not experience the fall of Rome.

It did not develop European feudalism in exactly the same form.

It did not experience the same relationship between church and monarchy.

So when we call this Korea's “early medieval” period, we are using the phrase mainly as a chronological comparison.

It helps answer our central question:

What was happening in Korea while Europe was entering its Middle Ages?

The answer is clear.

Korea was experiencing its own historical transformation—with its own political institutions, religions, cities, trade networks, and cultural achievements.

24. Why Unified Silla and Balhae Matter

This period transformed Korean history in several fundamental ways.

Unified Silla created a political and cultural framework integrating much of the peninsula.

Buddhism became deeply embedded in Korean culture.

Gyeongju emerged as an international city.

Art and architecture reached extraordinary levels of sophistication.

Maritime trade expanded.

Balhae continued important elements of the northern political world that had once belonged to Goguryeo.

Together, Silla and Balhae demonstrate that Korean history after the Three Kingdoms cannot be understood as the story of only one state.

The south and north followed different political paths.

Yet both were connected to a larger East Asian and Eurasian world.

25. Why This Still Matters Today

There is another reason this period matters.

It reminds us that Korea has rarely existed in isolation.

Silla's rise depended partly on an alliance with Tang China.

Its independence then required resistance against Tang power.

Balhae had to maintain relations with Tang, Japan, Silla, and northern peoples.

Merchants crossed seas.

Monks crossed borders.

Diplomats traveled between capitals.

Foreign goods reached Korean cities.

Korean ideas and technologies moved outward.

This combination of connection and strategic autonomy appears repeatedly in Korean history.

Modern circumstances are completely different.

But the geographic condition remains familiar.

Korea still sits between continental and maritime systems.

It still depends heavily on international trade.

And it still has to manage relations with powerful neighboring states while preserving its own political choices.

History does not repeat itself exactly.

But geography continues to shape the questions nations must answer.

26. When Vikings Sailed West, Korean Merchants Sailed East

Imagine the world around the year 830.

Viking ships were moving through European waters and along the great rivers of Eastern Europe.

Baghdad stood at the center of an enormous commercial and intellectual network.

The Byzantine Empire remained centered on Constantinople.

In Western Europe, Charlemagne's empire had recently passed to his successors.

And in East Asia:

Balhae ruled a vast northern territory.

Silla controlled most of the Korean Peninsula.

Jang Bogo's maritime network connected Korea, China, and Japan.

Buddhist monks traveled across borders.

Merchants moved across seas.

Gyeongju remained a major cultural center.

These were not separate histories occurring in different universes.

They were simultaneous chapters of the same human story.

The Story Continues

By the tenth century, both Silla and Balhae were gone.

In their place stood a new Korean dynasty.

Goryeo.

For nearly five centuries, Goryeo would rule Korea.

It would become famous for:

celadon ceramics,
Buddhist culture,
international trade,
monumental printing projects,
movable metal type,
and resistance to some of the most powerful armies Eurasia had ever seen.

And while Goryeo flourished in Korea, Europe would enter the age of:

castles, knights, feudal kingdoms, the Norman Conquest, and the Crusades.

The parallel becomes even more fascinating.

Next Episode

Goryeo and Medieval Europe: Two Worlds of the Middle Ages

What was Korea like when European knights rode to the Crusades?

While castles rose across Europe, another sophisticated medieval civilization was flourishing at the eastern end of Eurasia.

Its name would eventually give the modern world the word:

Korea.