عثمان غازى (ʿOsmān Ġāzī) / Osman Gazi
Osman Gazi was the leader of the Ottoman Turks and the founder of the Ottoman dynasty. His Beylik, while only a small principality during Osman’s lifetime, transformed into a world empire in the centuries after his death. It existed until shortly after the end of World War I. Historians commonly mark the end date at the abolition of the sultanate in 1922, the proclamation of the Republic of Turkey in 1923 or the abolition of the caliphate in 1924.
Some scholars have argued that Osman’s original name was Turkish, probably Atman or Ataman, and was only later changed to ʿOsmān, of Arabic origin. The earliest Byzantine sources, including Osman’s contemporary George Pachymeres, spell his name as Ατουμάν (Atouman) or Ατμάν (Atman), whereas Greek sources regularly render both the Arabic form ʿUthmān and the Turkish version ʿOsmān with θ, τθ, or τσ. An early Arabic source mentioning him also writes ط rather than ث in one instance. Osman may thus have adopted the more prestigious Muslim name later in his life.
Due to the scarcity of historical sources dating from his lifetime, very little factual information is known about him. Not a single written source survives from Osman’s reign. The Ottomans did not record the history of Osman’s life until the fifteenth century, more than a hundred years after his death. Because of this, it is very challenging for historians to differentiate between fact and myth in the many stories told about him. One historian has even gone so far as to declare it impossible, describing the period of Osman’s life as a “black hole.”
According to Stanford Shaw, Osman’s first real conquests followed the collapse of Seljuk authority when he was able to occupy the fortresses of Eskişehir and Karacahisar. Then he captured the first significant city in his territories, Yenişehir, which became the Ottoman capital. In 1302, after soundly defeating a Byzantine force near Nicaea, Osman began settling his forces closer to Byzantine controlled areas.
Alarmed by Osman’s growing influence, the Byzantines gradually fled the Anatolian countryside. Byzantine leadership attempted to contain Ottoman expansion, but their efforts were poorly organized and ineffectual. Meanwhile, Osman spent the remainder of his reign expanding his control in two directions, north along the course of the Sakarya River and southwest towards the Sea of Marmora, achieving his objectives by 1308. That same year his followers participated in conquest of the Byzantine city of Ephesus near the Aegean Sea, thus capturing the last Byzantine city on the coast, although the city became part of the domain of the Emir of Aydin.
Osman’s last campaign was against the city of Bursa. Although Osman did not physically participate in the battle, the victory at Bursa proved to be extremely vital for the Ottomans as the city served as a staging ground against the Byzantines in Constantinople and as a newly adorned capital for Osman’s son, Orhan.