Southeast Europe (909 BCE – 819 CE): Iron Kingdoms, Roman Frontiers, and Byzantine Beginnings

Regional Overview

Between the Adriatic and the Black Sea, Southeast Europe stood for a millennium as the hinge between the Mediterranean world and the steppe.
Its twin landscapes—the eastern Danubian–Thracian plains and the western Adriatic–Illyrian mountains—produced parallel yet intertwined histories.
Both absorbed Hellenic colonization, entered the Roman orbit, and later weathered the migrations that forged medieval Europe.
The region’s story from the early Iron Age to late Antiquity is thus one of fusion and frontier, where Greek, Roman, Thracian, Illyrian, and Slavic worlds met and reshaped one another.

Geography and Environment

The region divides naturally:

• Eastern Southeast Europe embraces the Lower Danube, Thracian plain, and Black Sea coast, enclosed by the Balkan and Carpathian arcs. Fertile lowlands sustained dense agrarian settlement, while the Danube served as both artery and barrier.

• Western Southeast Europe rises into karstic uplands and Adriatic coasts, with sheltered island chains and mountain basins suited to mixed farming and seaborne trade.

Climatic variation—humid along the coasts, continental inland—produced complementary economies: grain, salt, and metals from the east; timber, livestock, and maritime goods from the west.
Seasonal river floods and Adriatic storms shaped transport calendars; alpine passes and sea lanes linked every valley to the wider Mediterranean.

Societies and Political Developments

Greek Colonies and Indigenous Kingdoms

From the 8th to 5th centuries BCE, Greek settlers established poleis along both coasts: Apollonia and Dyrrhachium on the Adriatic; Odessos, Mesambria, and Histria on the Black Sea.
Behind them, Illyrian, Thracian, and Geto-Dacian tribes forged early kingdoms—the Odrysian realm in Thrace, the Ardiaean and Dardanian dominions in the west.
These polities traded metals, grain, and slaves for imported wine, oil, and ceramics, mediating between the Mediterranean and the interior.

Rome and the Imperial Frontier

Between the 2nd century BCE and the 1st century CE, Rome absorbed the entire peninsula: Macedonia, Illyricum, Dalmatia, Moesia, Thrace, and briefly Dacia north of the Danube.
Roman roads—the Via Egnatia, Via Militaris, and Sava-Drava corridors—stitched the provinces together.
Urban centers such as Salona, Skupi, Nicomedia, and Serdica reflected Roman law and architecture, while legionary camps and bridgeheads (Apollodorus’ bridge at Drobeta) turned the Danube into the empire’s longest fortified line.
Mining in Dacia, shipyards on the Adriatic, and grain estates in Moesia underpinned prosperity until the 3rd-century crises.

Migrations and the Byzantine Transition

From the 3rd to 7th centuries CE, the frontier dissolved under waves of Goths, Huns, Avars, and Slavs.
Cities were sacked, repopulated, and repurposed as Byzantine forts.
The Eastern Roman Empire, centered on Constantinople, re-emerged as the stabilizing power, holding Thrace and the coastal Adriatic while fostering Christianization.
By the late 7th century, the First Bulgarian Empire rose in Moesia and Thrace; Croatian and Serbian principalities took form in the western mountains, bridging the late antique and medieval orders.

Economy and Exchange

Agriculture remained the foundation:

• The Thracian plain and Wallachian lowlands exported grain and livestock along the Danube.

• The Adriatic coasts specialized in wine, oil, salted fish, and amphora industries.

• Mining of gold, silver, and iron in Dacia and the western ranges enriched both local chieftains and Roman prefects.

Trade routes—riverine, overland, and maritime—made the region a corridor between the Aegean, the Pannonian plain, and the steppe.
After Rome’s decline, Byzantine and Bulgar administrations preserved key arteries, ensuring continuity of commerce despite political fragmentation.

Technology and Material Culture

Iron metallurgy and Roman engineering reshaped daily life.
Stone bridges, aqueducts, and bath complexes signaled urban sophistication; rural estates used the iron plow to expand cultivation.
Local craftsmanship persisted: Thracian and Illyrian metalwork, Dacian goldsmithing, and later Slavic wood and textile arts.
Christian churches and monasteries, often rising atop pagan sanctuaries, announced new spiritual geographies while reusing classical masonry.

Belief and Symbolism

Religious life reflected the region’s pluralism:

• Indigenous cults—Zalmoxis, the Thracian Horseman—coexisted with Greek polytheism and Roman state worship.

• Christianity spread from urban bishoprics by the 4th century CE, producing early saints and councils.

• Slavic and Bulgar paganisms, with sky- and ancestor-deities, persisted until conversion in the 8th–9th centuries.
  Thus the region became a spiritual palimpsest, each new faith overlaying rather than erasing the old.

Adaptation and Resilience

Southeast Europe’s resilience lay in its geographical layering: river corridors, mountain refuges, and island coasts offered fallback zones in war or climate stress.
Agro-pastoral economies allowed mobility; fortified towns and hillforts provided refuge during invasions.
Byzantine fiscal systems and Bulgar tribute networks recycled Roman infrastructures, ensuring survival of settlement and trade patterns despite continual upheaval.

Regional Synthesis and Long-Term Significance

By 819 CE, Southeast Europe had completed its ancient cycle.
In the east, Byzantine Thrace and the Bulgar kingdom defined a Christian–steppe frontier along the Danube.
In the west, Slavic kingdoms grew amid the ruins of Roman Dalmatia, while the Adriatic cities preserved classical urbanism under imperial and papal influence.
Greek colonies, Roman provinces, and barbarian migrations had fused into a single cultural continuum—one that naturally divides into eastern (Danubian–Thracian) and western (Adriatic–Illyrian) spheres yet remains bound by geography, trade, and faith.

This equilibrium of coast and hinterland, empire and tribe, set the pattern for the medieval Balkans: a region perpetually contested but never peripheral, mediating between the Mediterranean world and the steppes beyond.

Eastern Southeast Europe (909 BCE – 819 CE) Early Iron & Antiquity — Greek Poleis, Thracians & Dacians, Rome & Byzantium, Migrations and Bulgars

Geographic and Environmental Context

Eastern Southeast Europe includes Turkey-in-Europe (Thrace); Greece’s Thrace; Bulgaria (except its southwest); Romania & Moldova; northeastern Serbia; northeastern Croatia; extreme northeastern Bosnia & Herzegovina.

• Anchors: Greek Black Sea poleis (Histria, Tomis/Constanța, Callatis/Mangalia, Odessos/Varna, Mesambria/Nessebar, Apollonia/Sozopol), Thrace (Odrysian kingdom), Moesia (Danube limes), Dacia(Transylvania & Wallachia), Lower Danube legionary line, Carpathian–Balkan passes.

Climate & Environmental Shifts

• First-millennium variability; fertile Thracian and Wallachian plains supported dense settlement; Danube avulsions required continual river management.

Societies & Political Developments

• Greek colonies flourished (7th–5th c. BCE) along the western Black Sea.

• Thracian Odrysian kingdom (5th–4th c. BCE) and Geto-Dacians north of the Danube rose to prominence.

• Rome annexed Moesia and Thrace; Dacia (106–271 CE) north of the Danube briefly Romanized with cities, mines, roads; Danube limes fortified.

• Migrations: Goths (3rd–4th c.), Huns (5th c.), Avars and Slavs (6th–7th c.) reconfigured the region;

• First Bulgarian Empire (from 681 CE) entrenched in Moesia/Thrace; Byzantium held Thrace and coastal cities.

Economy & Trade

• Grain, wine, salt, and livestock moved along the Danube; Black Sea ports exported to the Aegean–Mediterranean; mining (gold/silver in Dacia, iron in Thrace).

• Roman urbanism (roads, bridges e.g., Apollodorus’ bridge near Drobeta) integrated the frontier.

Technology & Material Culture

• Iron plowshares; Roman engineering; Thracian/Dacian metalwork; Byzantine fortifications.

• Urban mosaics, inscriptions, temples; later churches and monasteries.

Belief & Symbolism

• Thracian and Dacian cults (horseman, Zalmoxis); Greek polytheism; Roman state cults → Christianity (by late Roman/Byzantine era).

• Early Slavic and Bulgar paganisms persisted into 8th–9th c., gradually Christianizing.

Environmental Adaptation & Resilience

• Riverine transport and oasis agriculture stabilized supply; fortified towns and hillforts provided refuge; steppe pastoralism remained flexible under aridity pulses.

Legacy & Transition

By 819 CE, Eastern Southeast Europe was a braided frontier of Byzantine Thrace, Bulgar power, Slavic communities, and legacy Roman–Greek Black Sea cities. The Lower Danube’s fortified line, Thracian plain granaries, and coastal emporia formed the scaffolding for the medieval dynamics to come.

Eastern Southeast Europe (676–819 CE): Transformation, Division, and Regional Realignments

Settlement and Migration Patterns

Bulgarian and Slavic Territorial Consolidation

From 676 to 819 CE, Eastern Southeast Europe witnessed significant demographic and geopolitical changes. The establishment and expansion of the Bulgarian Empire, beginning with the inception of the first Bulgarian state around Pliska, led to major shifts. This expansion included territories eastward to the Black Sea, southward encompassing Macedonia, and northwestward reaching present-day Belgrade, reshaping regional settlement patterns dramatically.

Byzantine Territorial Challenges

Constantinople's control over the Balkans weakened significantly due to persistent Bulgarian pressures and shifting alliances. Despite substantial internal fortification efforts, the Byzantine Empire struggled to maintain its southern Balkan territories, facing increasing Slavic and Bulgarian influence.

Political and Military Developments

Bulgarian Ascendancy and Byzantine Retreat

Bulgarian political stability fluctuated, notably through a series of leadership crises, yet its territorial expansions continuously challenged Byzantine dominance. The Bulgarian Empire capitalized on Byzantine weaknesses, notably expanding after the Avars' defeat by Charlemagne, further diminishing Byzantine strategic influence.

Iconoclasm and Imperial Stability

Internally, the Byzantine Empire grappled with profound religious controversies, particularly Iconoclasm under Emperors Leo III and Constantine V. These theological disputes significantly influenced political stability, although Constantine V successfully enhanced military strength and internal administrative efficiency.

Charlemagne's Coronation and Diplomatic Realignment

Charlemagne's coronation in 800 CE symbolically restored the Western Roman Empire, permanently fracturing Byzantine aspirations of reunifying Christendom. The Byzantine Empire, after initial resistance, reluctantly recognized Charlemagne’s title, deepening the divide between Latin and Greek Christian traditions.

Economic and Technological Developments

Economic Adjustments Amid Geopolitical Shifts

Throughout this period, the economic landscape adapted to geopolitical upheavals. Bulgarian expansion altered trade routes and commercial dynamics, while Byzantine territories increasingly relied on enhanced fortifications and defensive technologies to secure economic stability.

Defensive Innovations

Both Byzantine and Bulgarian states prioritized military fortifications and defensive infrastructure. Strategic investments in defense, especially during Emperor Leo III and Constantine V’s reigns, ensured the survival and territorial integrity of their respective domains despite external threats.

Cultural and Artistic Developments

Cultural Exchanges and Adaptation

Cultural life thrived amid shifting political boundaries. Byzantine art, architecture, and religious practices experienced significant transformations due to Bulgarian and Slavic interactions. The Seventh Ecumenical Council’s restoration of icons in 787 CE marked a profound cultural shift, reinforcing traditional religious and artistic expressions.

Scholarly and Intellectual Resilience

Despite political disruptions, scholarly institutions maintained their critical roles, preserving classical, theological, and philosophical traditions. Intellectual continuity supported cultural resilience, adapting to new political and social contexts.

Social and Religious Developments

Religious Controversies and Ecclesiastical Divisions

The prolonged Iconoclast controversy deeply affected Byzantine society, notably under Leo III and Constantine V. Its resolution at the Seventh Ecumenical Council restored traditional icon veneration practices, reinforcing Eastern Orthodox identity and societal cohesion.

Strengthening of Eastern Orthodox Identity

Eastern Orthodoxy further solidified its role as a unifying social and religious force despite ongoing political fragmentation. Bulgarian territorial expansions introduced new social dynamics, compelling Eastern Orthodox institutions to adapt and reinforce their influential societal roles.

Long-Term Consequences and Historical Significance

The era from 676 to 819 CE was defined by transformative geopolitical shifts, critical religious controversies, and significant cultural exchanges. The establishment and expansion of the Bulgarian Empire, the Byzantine retreat from the Balkans, and the enduring religious impacts of Iconoclasm and Charlemagne’s coronation fundamentally reshaped Eastern Southeast Europe's historical trajectory, setting lasting regional dynamics and cultural identities.

East Central Europe (700–711 CE): Saxon Ascendancy, Slavic Consolidation, and Avar Stability

Between 700 and 711 CE, East Central Europe—encompassing Poland, Czechia, Slovakia, Hungary, and those portions of Germany and Austria lying east of 10°E and north of a line stretching from roughly 48.2°N at 10°E southeastward to the Austro-Slovenian border near 46.7°N, 15.4°E—entered a period marked by the rising prominence of the Saxons, continued consolidation of emerging Slavic principalities, and maintained stability within the Avar Khaganate. Saxon tribes expanded their territorial influence eastward, notably across eastern Germany, becoming significant players in regional geopolitics. Concurrently, Slavic political entities in Bohemia and Moravia further solidified their governance, while Thuringia sustained its autonomy from increasingly powerless Merovingian kings.

Political and Military Developments

Rise of Saxon Influence

• Saxon tribes, previously centered in northern and western Germany, extended their reach eastward, asserting dominance over territories east of the Elbe River. Their expansion significantly impacted regional politics, trade routes, and cultural interactions across eastern Germany and parts of western Poland.

Consolidation of Slavic Principalities

• Emerging Slavic political entities in Bohemia and Moravia continued their transition toward stable, early medieval state structures, strengthening local governance, defenses, and internal unity.

Continued Thuringian Autonomy

• Thuringia, under powerful local dukes, maintained de facto independence from weakened Frankish central authority. Merovingian kings remained incapable of reclaiming effective control, exemplifying the ongoing fragmentation of their royal power.

Stability within the Avar Khaganate

• The Avar Khaganate preserved political stability and territorial integrity within the Carpathian Basin, maintaining diplomatic relations with surrounding polities and carefully balancing interactions with increasingly influential Saxon and Slavic neighbors.

Economic and Technological Developments

Saxon Influence on Regional Trade

• Saxon eastward expansion stimulated regional trade, facilitating greater economic interaction across eastern Germany, Bohemia, Moravia, and parts of Poland. Trade goods included ironwork, agricultural produce, livestock, textiles, and craft products.

Continued Development of Defensive Infrastructure

• Saxons, Slavs, and Avars all continued developing fortified settlements, earthworks, and defensive systems, reflecting increased regional interaction and potential for military conflict.

Cultural and Artistic Developments

Saxon Cultural Expansion

• Saxon expansion eastward disseminated distinct Germanic cultural influences into previously Slavic and mixed territories. Saxon artistry, notably in metalworking, jewelry, and weaponry, became regionally influential.

Distinct Slavic Identities in Bohemia and Moravia

• Bohemian and Moravian communities further refined their distinctive regional cultural identities, evident in archaeological finds of pottery, jewelry styles, and settlement patterns.

Persistent Avar Cultural Influence

• The Avar cultural legacy continued prominently within the Carpathian Basin, influencing artistic traditions, especially metalwork, decorative arts, and equestrian equipment, across neighboring communities.

Settlement and Urban Development

Saxon Territorial Expansion and Settlement

• Saxon settlements proliferated eastward, establishing strategic strongholds, agricultural villages, and trading centers across eastern Germany and adjacent regions, notably impacting western Poland and northern Czechia.

Growth of Slavic Political Centers

• Fortified settlements and early urban centers expanded within Bohemia and Moravia, signaling increased political stability, population growth, and economic prosperity.

Stability in Bavarian and Thuringian Settlements

• Thuringian and Bavarian settlements, including significant towns such as Regensburg, remained prosperous and stable, benefiting from peaceful trade and reduced military threats.

Social and Religious Developments

Strengthened Saxon Tribal Hierarchy

• Saxon society featured strong tribal hierarchies, with powerful warrior elites dominating social, military, and economic life, facilitating cohesive expansion into East Central Europe.

Slavic Hierarchical Consolidation

• Slavic communities further centralized authority under increasingly powerful regional leaders, laying foundations for future state structures and organized defense.

Avar Sociopolitical Stability

• Within their core territory, the Avars maintained cohesive sociopolitical structures based around nomadic elite leadership, supported by a stable tribute economy.

Long-Term Consequences and Historical Significance

The era 700–711 CE represented a crucial transition marked by the rise of Saxon political and cultural influence, sustained consolidation among Slavic principalities, ongoing autonomy in Thuringia, and continued Avar stability. These developments significantly shaped the medieval political landscape, establishing enduring territorial patterns, ethnic identities, and economic networks in East Central Europe.

A Muslim army is invited into Ceuta by its governor, the possibly legendary Count Julian.

Roman Africa had been largely lost by the end of the seventh century to its Muslim conquerors, who in 711 seize the last outpost at Septem, where Julian, being an opponent of King Roderic of the Visigoths, encourages them to invade the Iberian peninsula.

According to the Egyptian historian Ibn Abd-el-Hakem, writing a century and a half after the events, Julian sent one of his daughters to Roderic's court at Toledo for education (and as a gauge of Julian's loyalty) and Roderic subsequently made her pregnant.

When Julian learned of the affair he removed his daughter from Roderic's court and, out of vengeance, betrayed Hispania to the Muslim invaders, thus making possible the Umayyad conquest of Hispania.

Later ballads and chronicles inflated this tale, Muslims making her out an innocent virgin who was ravished, Christians making her a seductress.

In Spanish she came to be known as la Cava Rumía, but this might well only be a legend.

Personal power politics were more likely at play, as better historical evidence points to a civil war among the Visigothic aristocracy.

Roderic had been appointed to the throne by the bishops of the Visigothic Catholic church—this appointment snubbing the sons of the previous king, Wittiza, who dies or is killed in 710; Wittiza's relatives and partisans had fled Iberia for Julian's protection at Ceuta (Septem), the Pillar of Hercules in North Africa on the northern shore of the Maghreb.

Here they have gathered with Arians and Jews fleeing forced conversions at the church's hands.

At this time, the surrounding area of the Maghreb had recently been conquered by Musa ibn Nusair, who has established his governor, Tariq ibn Ziyad, at Tangier with a Moorish army of seventeen hundred men.

Julian had therefore approached Musa to negotiate the latter's assistance in an effort to topple Roderic.

What is unclear is whether Julian hoped to place a son of Wittiza on the throne and gain power and preference thereby or whether he was intentionally opening up Iberia to foreign conquest.

The latter, though unlikely, isn't inconceivable, given that Julian may have long been on good terms with the Muslims of North Africa and found them to be more tolerant overlords than the Catholic Visigoths.

Moreover, if Julian was the Greek commander of the last imperial outpost in Africa, he would only have had an alliance with the Kingdom of the Visigoths rather than been part of it.

Perhaps, then, in exchange for lands in al-Andalus (the Arab name for the area the Visigoths still called by its Roman name, Hispania), or perhaps to topple a king and his religious allies, Julian provides military intelligence, troops, and ships.

Musa is initially unsure of Julian's project and so in July 710 directs Tarif ibn Malluk to lead a probe of the Iberian coast.

Legend says that Julian participated as a guide and emissary, arranging for Tarif to be hospitably received by supportive Christians—perhaps Julian's kinsmen, friends, and supporters—who agreed to become allies in the contemplated battle for the Visigothic throne.

Justinian's second reign is marked by a reconciliation with the papacy, cemented by the visit of Pope Constantine to Constantinople in 710-11.

The emperor is obsessed, however, with a desire for revenge against his opponents, and the resulting mass executions in turn have led to the alienation of many of his former supporters.

Bardanes is the son of the patrician Nicephorus, who was of Armenian extraction from an Armenian colony in Pergamon. (His original name, Vardan, may have been derived from that of his mother).

Relying on the support of the Monothelite party, he had made some pretensions to the throne on the outbreak of the first great rebellion against Emperor Justinian II; these had led to his relegation to Cephalonia by Tiberios Apsimarus, and subsequently to his banishment to Cherson by order of Justinian.

Here Bardanes, taking the name of Philippikos, has successfully incited the inhabitants to revolt with the help of the Khazars.

The successful rebels seize Constantinople, and Justinian flees.

Tervel gives the deposed emperor only three thousand soldiers who, after several skirmishes, are given safe conduct to Bulgaria by the new emperor and Justinian II, unable to rally substantial support in the provinces, is executed, together with his family, in December 711.

After resuming rule, Justininian had wreaked a vengeance so terrible that the fact of his second deposition and death is surprising only in it having been delayed for six years.

Philippikos takes the throne.

Julian provides the ships to carry Muslim troops across to Europe in the summer of 711.

Julian also briefs Tariq, their general, who then leaves Julian behind among the merchants and crosses the Strait of Hercules with a force of some seventeen hundred men.

Musa bin Nusayr, governor of the Muslim Arab city of Ceuta in northwestern Africa, responds in 711 to the request by the Witizan family to help them overthrow Roderick.

Seventeen hundred Umayyad Moorish troops led by Tariq ibn Ziyad land at Gibraltar on April 30, and begin their invasion of the Iberian Peninsula (Al-Andalus) and conquest of the Visigothic Kingdom.

(The name of the Spanish promontory later called Gibraltar derives from its Moorish designation, Jebel Tariq, or Mount Tariq, in honor of this conqueror of Spain.)

Muslim Berber general Tariq ibn Ziyad, dispatched by Musa across the Straits of Gibraltar, defeats Roderic on July 19, 711 at Laguna de Janda, near the Guadalete River (Rio Barbate).

Roderic attempts escape, but is either killed or drowned.

According to the Mozarabic Chronicle, Mūsā crossed the Gaditanum fretum (strait of Cádiz) with a large force in 711 and remained in Hispania for fifteen months, but it is unclear from the sources if he came before or after the battle of Guadalete, which was fought by the forces of his subordinates.

During his time in the peninsula it is racked by civil war (intestino furore confligeratur, "internal frenzy", to the Mozarabic chronicler), cities are razed and many people slaughtered in the general destruction.

According to al-Maqqarī, Roderic was fighting the Basques when he was recalled to the south to deal with an invasion.

There is also the record of a attack on southern Iberia by Constantinople that was repulsed by Theudimer some years before the fall of the Visigothic kingdom.

This has led to theories that the Berber attacks may have been related to the East Roman, and perhaps the Arabs were originally useful allies in an imperial attempt to reconquer the lost province of Spania.

Tariq, following his decisive victory over Roderick's Visigoths, takes the Andalusian port cities of Algeciras, …