Most historians believe that the Croats are a purely Slavic people who probably migrated to the Balkans from present-day Ukraine.

A newer theory, however, holds that the original Croats were nomadic Sarmatians who roamed Central Asia, migrated onto the steppes around 200 BCE, and rode into Europe near the end of the fourth century CE, possibly together with the Huns.

The Sarmatian Croats, the theory holds, conquered the Slavs of northern Bohemia and southern Poland and formed a small state called White Croatia near present-day Kraków.

The Croats then supposedly mingled with their more numerous Slavic subjects and adopted the Slavic language, while the subjects assumed the tribal name "Croat."

A tenth-century Byzantine source reports that in the seventh century Emperor Heraclius enlisted the Croats to expel the Avars from Byzantine lands.

The Croats had overrun the Avars and Slavs in Dalmatia around 630, then drove the Avars from today's Slovenia and other areas.

In the eighth century, the Croats lived under loose imperial rule, and Christianity and Latin culture recovered in the coastal cities.

The Franks subjugated most of the Croats in the eighth century and sent missionaries to baptize them in the Latin rite, but the Byzantine Empire continued to rule Dalmatia.

Croatia emerges as an independent nation in 924.

Tomislav (910-ca. 928), a tribal leader, establishes himself as the first king of Croatia, ruling a domain that stretches eastward to the Danube.

The Slovenes, Croats, Serbs, Montenegrins, Bosnians, Macedonians, and Albanians have virtually independent histories.

The Slovenes will struggle to define and defend their cultural identity for a millennium, first under the Frankish Kingdom and then under the Austrian Empire.

The Croats of Croatia and Slavonia will enjoy a brief independence before falling under Hungarian and Austrian domination; and the Croats in Dalmatia struggle under Byzantine, Hungarian, Venetian, French, and Austrian rule.

The Serbs, who will briefly rival the Byzantine Empire in medieval times, will suffer five hundred years of Turkish domination before winning independence in the nineteenth century.

Their Montenegrin kinsmen will live for centuries under a dynasty of bishop-priests and savagely defend  their mountain homeland against foreign aggressors.

Bosnians will turn to heresy to protect themselves from external political and religious pressure, convert in great numbers to Islam after the Turks invade, and become a nuisance to Austria-Hungary in the late nineteenth century.

A hodgepodge of ethnic groups will people Macedonia over the centuries.

As the power of the Ottoman Empire wanes, the region is contested among the Serbs, Bulgarians, Greeks, and Albanians and also is a pawn among the major European powers.

Finally, the disputed Kosovo region, with an Albanian majority and medieval Serbian tradition, will remain an Ottoman backwater until after the Balkan wars of the early twentieth century.

Additional turmoil erupts when the Ottoman Turks expand their empire into the Balkans.

They cross the Bosporus Straits in 1352, subdue Bulgaria in 1388, and defeat the Serbs at Kosovo Polje in 1389.

Sigismund leads a crusade against them in 1396, but the Ottomans rout his forces at Nicopolis, and he barely escapes with his life.

Tamerlane's invasion of Anatolia in 1402-03 slows the Turks' progress for several decades, but in 1437 Sultan Murad prepares to invade Hungary.

Sigismund dies the same year, and Hungary's next two kings, Albrecht V of Austria (1437-39) and Wladyslaw III of Poland (1439-44), who is known in Hungary as Ulaszlo I, both die during campaigns against the Turks.

After Ulaszlo, Hungary's nobles choose an infant king, Laszlo V, and a regent, Janos Hunyadi, to rule the country until Laszlo V comes of age.

The son of a lesser nobleman of the Vlach tribe, Hunyadi has risen to become a general, Transylvania's military governor, one of Hungary's largest landowners, and a war hero.

He uses his personal wealth and the support of the lesser nobles to win the regency and overcome the opposition of the magnates.

Hunyadi then establishes a mercenary army funded by the first tax ever imposed on Hungary's nobles.

He defeats the Ottoman forces in Transylvania in 1442 and breaks their hold on Serbia in 1443, only to be routed at Varna (where Laszlo V himself perishes) a year later.

In 1456, when the Turkish army besieges Belgrade, Hunyadi defeats it in his greatest and final victory.

Hunyadi dies of the plague soon after.

When Ulaszlo II dies in 1516, his ten-year-old son Louis II (1516-26) becomes king, but a royal council appointed by the Diet rules the country.

Hungary is in a state of near anarchy under the magnates' rule.

The king's finances are a shambles; he borrows to meet his household expenses despite the fact that they total about one-third of the national income.

The country's defenses sag as border guards go unpaid, fortresses fall into disrepair, and initiatives to increase taxes to reinforce defenses are stifled.

In 1521 Sultan Suleiman the Magnificent recognizes Hungary's weakness and seizes Belgrade in preparation for an attack on Hungary.

In August 1526, he marches more than one hundred thousand troops into Hungary's heartland, and at Mohacs they cut down all but several hundred of the twenty-five thousand ill-equipped soldiers whom Louis II had been able to muster for the country's defense.

Louis himself dies, thrown from a horse into a bog. 

Matyas regularly convenes the Diet and expands the lesser nobles' powers in the counties, but he exercises absolute rule over Hungary by means of a secular bureaucracy.

He enlists thirty thousand foreign mercenaries in his standing army and builds a network of fortresses along Hungary's southern frontier, but he does not pursue his father's aggressive anti-Turkish policy.

Instead, Matyas launches unpopular attacks on Bohemia, Poland, and Austria, pursuing an ambition to become Holy Roman Emperor and arguing that he is trying to forge a unified Western alliance strong enough to expel the Turks from Europe.

He eliminates tax exemptions and raises the serfs' obligations to the crown to fund his court and the military.

The magnates complain that these measures reduce their incomes, but despite the stiffer obligations, the serfs consider Matyas a just ruler because he protects them from excessive demands and other abuses by the magnates.

He also reforms Hungary's legal system and promotes the growth of Hungary's towns.

Matyas is a true renaissance man and makes his court a center of humanist culture; under his rule, Hungary's first books are printed and its second university is established.

Matyas's library, the Corvina, is famous throughout Europe.

In his quest for the imperial throne, Matyas eventually moves to Vienna, where he dies in 1490.

The Diet of 1514, shocked by the peasant revolt, passes laws that condemn the serfs to eternal bondage and increase  their work obligations.

Corporal punishment becomes widespread, and one noble even brands his serfs like livestock.

The legal scholar Stephen Werboczy includes the new laws in his Tripartitum of 1514, which will make make up Hungary's legal corpus until the revolution of 1848.

The Tripartitum give Hungary's king and nobles, or magnates, equal shares of power: the nobles recognize the king as superior, but in turn the nobles have the power to elect the king.

The Tripartitum also frees the nobles from taxation, obligates them to serve in the military only in a defensive war, and makes them immune from arbitrary arrest.

The new laws weaken Hungary by deepening the rift between the nobles and the peasantry just as the Turks prepare to invade the country.

Matyas's reforms do not survive the turbulent decades that follow his reign.

An oligarchy of quarrelsome magnates gains control of Hungary.

They crown a docile king, Vladislav Jagiello (the Jagiellonian king of Bohemia, who is known in Hungary as Ulaszlo II, 1490-1516), only on condition that he abolish the taxes that had supported Matyas's mercenary army.

As a result, the king's army disperses just as the Turks are threatening Hungary.

The magnates also dismantle Matyas's administration and antagonizes the lesser nobles.

In 1492 the Diet limits the serfs' freedom of movement and expands their obligations.

Rural discontent boils over in 1514 when well-armed peasants under Gyorgy Dozsa rise up and attack estates across Hungary.

United by a common threat, the magnates and lesser nobles eventually crush the rebels.

Dozsa and other rebel leaders are executed in a most brutal manner.

Southeast Europe (1396–1539 CE)

Ottoman Ascendancy, Balkan Frontiers, and the Fault Line of Christendom

Geography & Environmental Context

Southeast Europe in this era was a land of rivers, mountains, and fortified cities dividing Christian and Islamic worlds.
Eastern Southeast Europe stretched from Turkey-in-Europe and Thrace through Bulgaria, Moldova, and Romania to the Danube Delta—a landscape of river valleys, forest plains, and mountain ramparts feeding into the Bosporus and the Black Sea.
Western Southeast Europe encompassed Greece, Albania, Montenegro, North Macedonia, Kosovo, Bosnia, Croatia, and Slovenia, where the Dinaric Alps, Pindus, and Adriatic coasts met the mountain hinterlands of the Balkans.
This region formed the great hinge between Central Europe and the eastern Mediterranean, a crossroads of empires and faiths.

Climate & Environmental Shifts

The Little Ice Age cooled the region, tightening agricultural margins:

• Danube Basin: Floods alternated with droughts, reshaping floodplain farming.

• Carpathian & Balkan uplands: Heavy snow prolonged transhumance cycles; spring torrents enriched meadows.

• Thrace & Aegean coasts: Frosts damaged olives and vines; Mediterranean crops retreated upslope.

• Adriatic & Ionian Seas: Stormier seasons and colder currents complicated navigation and coastal trade.

Subsistence & Settlement

• Plains & river valleys: Wheat, barley, rye, and millet formed staples; vineyards in Bulgaria and Thrace produced wine for local and export trade.

• Uplands: Sheep, goats, and cattle moved along seasonal routes between the Carpathians, Balkans, and Dinaric Alps.

• Coasts & islands: Olive oil, figs, salt, and fisheries supported maritime towns from Dubrovnik to Thessaloniki.

• Mining zones: Bosnia and Serbia exported silver and lead via Dalmatian ports.

• Urban nodes: Constantinople/Istanbul, Sofia, Iași, Belgrade, and Dubrovnik were vital centers of administration, craft, and exchange.

Technology & Material Culture

• Agriculture: Iron-tipped plows and watermills improved productivity; Ottoman timar tenure reorganized rural estates.

• Military: Gunpowder artillery transformed sieges; the Ottomans perfected field logistics and fortress artillery; local principalities deployed cavalry and wagon defenses.

• Architecture: Frescoed Orthodox monasteries such as Voroneț and Humor adorned Moldavia; Ottoman mosques, baths, and bridges reshaped Balkan towns; Venetian Gothic façades persisted on the Adriatic.

• Crafts: Balkan goldsmithing, woodcarving, and textile production continued under mixed Ottoman and local patronage.

Movement & Interaction Corridors

• The Danube Corridor: Lifeline for armies, grain, and trade; fortresses like Belgrade and Vidin guarded crossings.

• Via Egnatia & Balkan passes: Connected Adriatic ports with Thrace and Constantinople, sustaining overland caravans.

• Black Sea–steppe routes: Linked Moldavia, Dobruja, and the Crimea, feeding Ottoman supply lines.

• Adriatic and Aegean sea lanes: Carried Venetian, Ragusan, and Ottoman fleets, merchants, and pilgrims between Italy, Greece, and Anatolia.

• Mountain and forest roads: Enabled transhumance and the smuggling of goods and people across imperial frontiers.

Cultural & Symbolic Expressions

• Orthodox Christianity: Monasteries in Moldavia, Wallachia, Serbia, and Athos preserved liturgy, manuscript illumination, and identity under Ottoman rule.

• Islamic urban culture: Mosques, caravanserais, and vakıf foundations spread through conquered towns, introducing Ottoman civic life.

• Catholic & Humanist enclaves: Dalmatian cities like Zadar, Split, and Dubrovnik maintained Latin schools and libraries; émigré scholars from Constantinople brought Greek manuscripts to Italy, fueling the Renaissance.

• Folk traditions: Heroic songs of Hunyadi, Skanderbeg, and Stephen the Great celebrated resistance; South Slavic and Albanian epics sustained oral memory.

• Civic artistry: Icon painting, manuscript copying, and folk embroidery bridged church and household devotion.

Environmental Adaptation & Resilience

• Agrarian diversity: Mixed grain, vine, and pastoral systems buffered risk; maize was still unknown but cereals diversified diets.

• Transhumant mobility: Pastoralists followed snowmelt, shifting herds between alpine meadows and Danubian plains.

• Forest refuge: Villages rebuilt after raids amid forest cover; woodlands supplied construction and fuel.

• Maritime exchange: Salt, fish, and ship timber stabilized economies when inland fields failed.

• Ottoman provisioning networks: Redirected Balkan surpluses toward Istanbul and garrisons, maintaining trade under imperial integration.

Technology & Power Shifts (Conflict Dynamics)

• Ottoman victories:

  • Nicopolis (1396) and Varna (1444) shattered crusader resistance.

  • Constantinople fell in 1453, transforming it into Istanbul.

  • Belgrade (1521) and Mohács (1526) opened Hungary to Ottoman partition.

• Danubian principalities: Wallachia and Moldavia maintained tributary autonomy; leaders like Mircea the Elderand Stephen the Great resisted Ottoman and Tatar incursions.

• Crimean Tatars: Allied with the Ottomans, raided Moldavia, Poland, and Ukraine, feeding the Black Sea slave trade.

• Western frontiers: Venice clashed with Ottoman fleets; Dubrovnik navigated neutrality and profit as intermediary; Skanderbeg’s Albanian revolt (1443–1468) became emblematic of mountain resistance.

• Naval dominance: The Battle of Preveza (1538) secured Ottoman mastery of the Ionian and Aegean seas.

Transition (to 1539 CE)

By 1539, Southeast Europe had become the principal marchland of empire.
The Ottoman crescent stretched from the Danube to the Aegean and Adriatic, with Istanbul at its center.
Bulgaria, Thrace, Greece, and Bosnia were integrated into Ottoman administration; Wallachia and Moldavia paid tribute; Transylvania balanced between Habsburg and Ottoman influence.
The Adriatic remained contested—Venice held coastal enclaves, while Dubrovnik thrived as a neutral broker.
Amid conquest, Balkan peoples preserved faith, language, and tradition through monastery, market, and mountain refuge.
The age closed with the Battle of Preveza (1538) and Ottoman control of the eastern Mediterranean, confirming Southeast Europe as the heart of the empire’s European frontier—a landscape of faith, resistance, and imperial transformation.

Eastern Southeast Europe (1396–1539 CE): Ottoman Ascendancy, Danubian Principalities, and Balkan Crossroads

Geographic & Environmental Context

The subregion of Eastern Southeast Europe includes Turkey-in-Europe, Thrace-in-Greece, Bulgaria (except the southwest), Moldova, Romania, northeastern Serbia, northeastern Croatia, and extreme northeastern Bosnia and Herzegovina. Anchors included the Danube from the Iron Gates to its delta, the Wallachian and Moldavian plains, the Transylvanian and Carpathian margins, the Balkan and Rhodope ranges, and the Thracian plain leading to Constantinople/Istanbul. This was a meeting ground of steppe and forest, mountain fortresses and river valleys, bound by the Danube corridor and the Bosporus straits.

Climate & Environmental Shifts

The Little Ice Age cooled winters and shortened growing seasons.

• Danube basin: spring floods inundated floodplains; summer droughts alternated with wet years, affecting grain surpluses.

• Carpathian foothills & Balkan uplands: heavy snowpack fed torrents; pastoralists shifted grazing with snowmelt.

• Thrace & Marmara lowlands: Mediterranean crops of vines and olives endured but suffered frost in severe winters.

Subsistence & Settlement

• Rural farming: Wheat, barley, millet, and rye across Wallachia, Moldavia, and Thrace; vineyards in Bulgaria and Thrace; maize only arrived later.

• Pastoralism: Sheep, cattle, and horses grazed on plains and upland meadows; transhumance between Carpathians and lowlands.

• Towns & trade nodes: Constantinople/Istanbul, Sofia, Târgu Jiu, Bucharest (emerging), Iași, and Brașov; fortified citadels guarded Danube crossings.

• Fishing & forests: Danube, Prut, and Dniester supplied sturgeon and carp; forests yielded honey, wax, and timber.

Technology & Material Culture

• Agriculture: Wooden plows, iron-tipped tools, watermills; peasant strips and manorial estates persisted under Ottoman timar and local boyar systems.

• Military: Cavalry and fortresses dominated warfare; Ottomans refined siege artillery; Moldavian and Wallachian hosts combined light cavalry with war wagons.

• Crafts & architecture: Orthodox monasteries in Moldavia and Wallachia (Voroneț, Humor) painted with vivid frescoes; Ottoman mosques and baths began reshaping Balkan towns.

Movement & Interaction Corridors

• Danube corridor: Lifeline for grain, salt, and armies; Brașov and Belgrade were major crossings.

• Black Sea–steppe routes: Moldavia and Dobruja linked to Genoese colonies (until Ottoman conquest in 1475) and later Ottoman trade.

• Balkan passes: Shipka and Iron Gates moved caravans between plains and coastal zones.

• Ottoman expansion: After Battle of Nicopolis (1396) and Varna (1444), Ottomans pressed north; 1453 capture of Constantinople secured the Bosporus; Belgrade resisted until 1521.

Cultural & Symbolic Expressions

• Orthodoxy: Wallachia, Moldavia, and Bulgaria maintained Orthodox liturgy, monasteries, and saints’ cults as centers of identity under Ottoman suzerainty.

• Ottoman Islam: Spread in towns via mosques, markets, and administrative complexes; janissary garrisons became cultural nodes.

• Humanism: Latin and Greek scholars fled Constantinople (1453), carrying manuscripts to Italy; Balkan literacy endured in monasteries.

• Epic & folklore: Songs of resistance (Hunyadi, Skanderbeg) circulated; Moldavian chronicles preserved local memory.

Environmental Adaptation & Resilience

• Farmers: Diversified between cereals, vineyards, and pastoralism; stored grain in earth cellars.

• Pastoralists: Practiced flexible transhumance, moving flocks between Carpathian pastures and Danubian lowlands.

• Villages: Rebuilt after raids with timber palisades; forests offered refuge.

• Markets: Redistributed surpluses; Ottoman provisioning drew resources toward Istanbul and military roads.

Technology & Power Shifts (Conflict Dynamics)

• Ottoman victories: Nicopolis (1396), Varna (1444), Kosovo (1448), Constantinople (1453), Belgrade (1521), Mohács (1526).

• Danubian principalities: Wallachia and Moldavia maintained tributary autonomy, resisting at times (Mircea the Elder, Stephen the Great of Moldavia defeated Ottomans at Vaslui, 1475).

• Hungary & Habsburgs: Held the northern frontier until Mohács (1526), after which Ottomans partitioned Hungary and pressed into the Carpathian basin.

• Crimean Tatars: Allied to Ottomans, raided Moldavia, Poland, and Ukraine through Black Sea steppes.

Transition

By 1539 CE, Eastern Southeast Europe had become an Ottoman marchland. Constantinople was the Ottoman capital, Bulgaria and Thrace integrated into the timar system, and Belgrade secured. Wallachia and Moldavia remained tributary but strategically vital; Transylvania, now semi-independent, stood between Ottoman and Habsburg spheres. The Danube and Carpathian arc had become Europe’s central fault line between Christendom and the expanding Ottoman world.