Byzantine Prusa, taken by Orhan in 1326 and made the first Ottoman capital: the burial city of the first six Ottoman rulers, whose royal mosque complexes and silk markets survive from the fourteenth and fifteenth centuries.
Bursa lies on the lower slopes of Uludağ, the Mysian Olympus of antiquity, above a fertile plain running down toward the Sea of Marmara. As Byzantine Prusa it was a walled town known for its hot springs; taken by the Ottomans in 1326, it became the first real capital of their state and the burial place of its first six rulers.
Its early Ottoman buildings survive in unusual numbers. Orhan built his mosque and market in the lower town, and Murad I, Bayezid I, Mehmed I and Murad II each founded a complex of mosque, madrasa, kitchen and bath on a separate site to the west or east, so that the town grew outward to join them.
The ancient town took its name from a king Prusias of Bithynia, and under Roman rule it was a modest place whose public baths Pliny the Younger discussed in his letters to Trajan in about 110. In the Byzantine centuries Prusa was a walled town on a rocky spur, overshadowed by the great Bithynian cities of Nicomedia and Iznik.
After 1204 Prusa belonged to the Empire of Nicaea, the Byzantine successor state that held western Anatolia until its rulers recovered Constantinople in 1261. The return of the court to the Bosphorus left the Bithynian frontier short of troops and money, and by the 1290s Turkish frontier lords, among them Osman, were raiding the countryside around the town.
Osman I had no siege engines, so he isolated the city. After his victory over a Byzantine force at the Battle of Bapheus in 1302, Ottoman tradition says he built forts facing Prusa to cut it off from its fields, and the blockade dragged on while the empire was distracted by the civil war between Andronikos II and his grandson. Starved out, the city surrendered to Osman's son Orhan on 6 April 1326. Osman died about the same time and was buried in the citadel, by tradition at his own wish.
Orhan made Bursa the capital of a state that soon reached the Marmara, taking Iznik in 1331 and Nicomedia in 1337. The first Ottoman silver coins are traditionally said to have been struck there, and in 1339 he built below the citadel a mosque, a bath and an inn whose rents supported them, the start of the commercial lower town. Ibn Battuta, who came in the early 1330s, described a great city with fine markets and broad streets surrounded by gardens and springs, and called Orhan the greatest of the Turkmen rulers in wealth, lands and troops.
After the conquest of Adrianople in the 1360s, Edirne gradually replaced Bursa as the sultans' main residence, but Bursa kept the dynasty's tombs and its markets. Murad I built his mosque at Çekirge by the hot springs, a two-storey building with a madrasa on the upper floor, and after he was killed at the Battle of Kosovo in 1389 his body was brought back and buried beside it.
Bayezid I built a complex on the eastern hill of Yıldırım in about 1390–1395, and after his victory at the Battle of Nicopolis in 1396 he raised the Great Mosque, the Ulu Cami, in the lower town between 1396 and 1400; by a later story its twenty domes stood in for the twenty mosques he had vowed for the victory. In 1402 Timur destroyed Bayezid's army at the Battle of Ankara, and Timur's grandson Muhammad Sultan rode on to Bursa, which was plundered and burned.
During the eleven years of civil war among Bayezid's sons, Bursa changed hands several times. Mehmed Çelebi took it from his brother İsa in 1403, and in about 1413 the Karamanid ruler Mehmed Bey besieged the city and burned the lower town. Once the state was reunited under Mehmed I, the Ottomans rebuilt: his Green Mosque, begun in 1412 and finished in 1419 or 1420, was decorated with tiles signed as the work of the masters of Tabriz, and he was buried in 1421 in the Green Tomb beside it.
Murad II built the last of the royal complexes, the Muradiye, west of the city, its mosque completed in 1426, and asked in his will to lie there under a dome open to the sky; he was buried there in 1451. After 1453 Istanbul was the capital, but Bursa remained the chief city of Ottoman Anatolia. In 1481 Mehmed II's younger son Cem was proclaimed sultan there against his brother Bayezid II; defeated, he fled to the Knights Hospitaller, and his body was brought back from Italy to the Muradiye in 1499.
Osman I and Orhan lie in the citadel, in tombs rebuilt after the earthquake of 1855 on the site of a converted Byzantine church, while Murad I, Bayezid I, Mehmed I and Murad II lie beside their own foundations, and the Muradiye also holds the tombs of Cem and other princes. Emir Sultan, a Sufi from Bukhara who married a daughter of Bayezid I, gave his name to the mosque and cemetery on the eastern side of the city that became a place of pilgrimage.
Süleyman Çelebi, imam at a mosque of Bayezid I, completed in 1409 his Mevlid, the Turkish poem on the birth of the Prophet that is still recited at memorial gatherings in Turkey. The Burgundian traveller Bertrandon de la Broquière spent ten days in the city in 1432, lodging with a Florentine merchant, and left for Constantinople with a company of Spanish and Florentine traders.