Imperial Ottoman

History · In depth

The Rise of the Ottoman Empire

The origins and early expansion of the Ottoman state from a small frontier principality under Osman I to the conquest of Constantinople in 1453.

The Ottoman state was founded in the closing years of the thirteenth century, but the foundations on which it grew were laid much earlier. To follow the rise of the Ottomans is to trace a small Turkic frontier principality from a band of gazi warriors into the dominant power of the eastern Mediterranean by 1453. The overview of Ottoman history is set out in the main article; this one focuses on the period 1299 to 1453 in detail.

The Seljuk inheritance

The Seljuk Sultanate of Rum had been the principal Turkish power in Anatolia since the late eleventh century. By the early thirteenth, however, it had been reduced to a vassal of the Mongol Ilkhanate after the Battle of Köse Dağ in 1243. As Mongol authority weakened in the late 1200s, the Seljuk state fragmented into a patchwork of beyliks, small principalities ruled by warlords of Turkmen origin.

In the far northwest of this fragmented Anatolia, near the Byzantine frontier, the Kayı clan under Ertuğrul held a marchland against the shrinking empire. The sources for Ertuğrul’s life are thin and partly legendary, but the tradition that his family received lands at Söğüt from the Seljuks in return for frontier service is consistent with the gazi ethos of the region. His son Osman I inherited this patrimony around the death of Ertuğrul in c. 1281.

The gazi tradition shaped the early Ottoman state in decisive ways. The gazi was a frontier warrior who fought in the name of Islam and who was rewarded with plunder, land, and the prestige of religion. In a region of constant war between the Byzantine frontier and the Turkmen heartland, the gazi ethos provided a powerful vocabulary of legitimacy that could attract warriors, settle nomads, and incorporate the existing religious establishment into a new political order.

Osman I and the founding of a dynasty

The conventional date for the founding of the Ottoman state is 1299, when Osman declared independence from the Seljuk sultanate, but the state remained tiny for a generation. Osman’s chief military advantage was his position on the Byzantine frontier, where he could raid the rich agricultural lands of Bithynia and recruit followers from among the Turkish nomads migrating into western Anatolia. The early Ottoman economy depended heavily on plunder and on the gazi ethic that framed this plunder as a religious duty.

Osman is also credited with the introduction of the distinctive white turban that would become a dynastic symbol. The famous dream of the moon entering his body, in which a sheikh foretold that Osman and his descendants would rule over a vast empire, became a foundational myth of the dynasty. The chronology of his reign is uncertain in detail, but by the time of his death around 1326, his state had grown into the most important of the western Anatolian beyliks.

Osman’s relationship with the Byzantine frontier was more complex than the gazi myth suggests. He formed alliances with local Byzantine lords, married into the families of neighboring Turkish beyliks, and at various points served the Byzantine emperor as a client. The famous Bapheus, or Koyunhisar, victory of around 1302 demonstrated that the Ottoman forces could defeat a Byzantine army in open battle, and it marked the transition from raiding to territorial expansion. The transition was gradual, but by the end of Osman’s reign the principality had a settled population, a regular income from agriculture, and a reputation that attracted volunteers from across the Turkish world.

Orhan and the first capital

Osman’s son Orhan captured Bursa in 1326, making it the first Ottoman capital. Within a few years, the Ottomans had taken Nicaea and Nicomedia, and their raiders were crossing into Thrace. The famous crossing of the Dardanelles in 1354, in which the Ottomans took the Gallipoli peninsula after an earthquake weakened its defenders, opened the road to Europe.

Orhan’s reign also saw the establishment of many of the institutions that would define Ottoman governance. He expanded the army by adopting the iqta’ system of land grants for cavalry, and he organized infantry using the devshirme levy that would later supply the Janissary corps. He also married Theodora, the daughter of a Byzantine prince, although the details and even the existence of this marriage are debated. By the time of his death around 1362, the principality had grown into a regional power with possessions in both Anatolia and Europe.

The Ottoman takeover of Bursa was a turning point in the urbanization of the principality. The city, which had been a major Byzantine commercial center, was settled by Turkmen families and developed into the first major Ottoman center of trade, religion, and administration. The pious foundations established by Orhan and his successors supported mosques, schools, and soup kitchens that made Bursa into a magnet for further migration. The model would be repeated in Edirne, in Istanbul, and in cities across the empire.

The crossing into Europe

The crossing of the Dardanelles in 1354 was a turning point. Within twenty years, the Ottomans had seized Adrianople (Edirne), which Orhan’s son Murad I made the new capital. The first major Ottoman campaign in the Balkans culminated in the Battle of Maritsa in 1371, in which a coalition of Serbs, Bosnians, Albanians, and Hungarians was routed. By the time of Murad I’s death at the Battle of Kosovo in 1389, the Ottomans were the dominant power in the southern Balkans.

The Battle of Kosovo has been heavily mythologized, both in Serbian and in Turkish national memory. The death of both Murad and the Serbian prince Lazar shaped the field. Although the immediate Serbian counter-attack was contained, the battle established Ottoman prestige and made further expansion into the interior possible. The marriage of Murad’s son Bayezid to a Serbian princess was a foretaste of the policy of integrating Balkan elites into the Ottoman ruling class.

The integration of the Balkans was as much an administrative and demographic as a military process. Murad and his successors settled Turkmen nomads in the conquered lands, granted timar fiefs to the cavalry, and incorporated the local Christian aristocracy into the Ottoman system as long as they paid tribute and provided service. The devshirme levy, which took Christian boys for service in the Janissary corps and the palace, was both a tool of social mobility and a source of resentment among subject populations, but it was also a powerful instrument of integration. The devshirme, the timar, and the imperial diwan would prove durable enough to carry the empire from this period through the Ottoman golden age and into the long crisis of the seventeenth and eighteenth centuries.

Bayezid I and the Ottoman Interregnum

Bayezid I, called the Thunderbolt, expanded the empire in every direction, but his ambition brought him into conflict with Timur, the Central Asian conqueror. The Battle of Ankara in 1402 was a catastrophe. Bayezid was captured, and the empire descended into civil war among his sons, an interregnum that lasted from 1402 to 1413.

The interregnum is sometimes called the fetal position of the Ottoman state. The European possessions held in many cases, but the Anatolian beyliks reasserted their independence. The Greek cities of the Aegean coast reverted to Venetian or local control. The empire’s survival owed much to the ability of Mehmed I, who reunified the state in 1413, to balance the competing claims of his brothers and to rebuild a working administration. Mehmed I, sometimes called the second founder of the empire, was a master of diplomatic compromise who used marriage alliances, religious legitimation, and a network of loyal officials to hold the state together.

Murad II and the recovery

Murad II, who reigned from 1421 to 1451 with an interval of abdication, restored the empire to its earlier trajectory. He defeated a coalition of Hungarians and Serbian despots at the Battle of Varna in 1444, ending the last major crusade against the Ottomans. The Albanian resistance under Skanderbeg occupied a great deal of Ottoman attention, but the death of Skanderbeg in 1468 and the surrender of the Albanian strongholds in the 1470s ended organized resistance.

Murad also began the demographic and economic transformation of the empire. He settled Turkmen nomads in the Balkans, established vakıf, or pious endowment, institutions to fund mosques and schools, and rebuilt the army along lines that would carry it through the next century. By the time of his death, the empire was once again expanding on all fronts.

The period of Murad’s reign also saw the slow development of Ottoman gunpowder warfare. The use of cannon, which had been pioneered in the late fourteenth century, was refined in the fifteenth. The great bombard cast by Orban in 1452, capable of hurling a stone ball of several hundredweight, was a milestone in the development of siege artillery and a foretaste of the kind of firepower that would be used against Constantinople a year later.

The road to Constantinople

The Byzantine Empire, by the mid-fifteenth century, was reduced to a small territory around Constantinople, a few islands in the Aegean, and the Peloponnese. Its emperors had long paid tribute to the Ottomans and had long served as clients of the Porte. The last emperor, Constantine XI, came to the throne in 1449 with the explicit aim of preserving what remained.

Mehmed II’s accession in 1451, at the age of nineteen, marked a new determination. The young sultan spent his first two years preparing an enormous army, a large fleet, and a massive siege train that included the famous bombard cast by Orban. The defense of Constantinople has been told many times; the city held out for fifty-three days before the final assault on 29 May 1453. The fall of Constantinople is treated in its own article, but for the purposes of the rise of the empire it is the decisive moment: it ended the Byzantine Empire, established the Ottomans as a world power, and gave them a capital of unmatched symbolic and strategic importance.

The shape of the early empire

By 1453, the Ottoman state looked very different from the small principality of 1299. It had developed a sophisticated fiscal system, a standing infantry, a religious establishment, and a tradition of conquest that would carry it to the gates of Vienna within a century. The institutions developed in this period, the devshirme, the timar cavalry, the imperial diwan, and the religious endowments, would outlast the empire itself and shape the early modern Middle East for centuries.

The rise of the empire, then, was not the work of a single ruler or even a single dynasty. It was the cumulative result of migrations, conquests, marriages, and the patient building of institutions over more than a century and a half. The next phase, the great expansion of 1453 to 1600 described in the Ottoman golden age, was possible only because the foundations had been laid so carefully in the period surveyed here. The long decline and reform of the seventeenth and eighteenth centuries, and the eventual end of the Ottoman Empire, would be shaped in turn by the institutions and ambitions built during this formative period. The long arc of expansion that began here eventually reached Hungary, where the Battle of Mohács of 1526 was the decisive moment, and ended in the territorial losses recorded in the Treaty of Karlowitz of 1699.