Founding of the Ottoman Beylik

Name: Founding of the Ottoman Beylik
Start: 1299

Type Event Region Anatolia Time 1299

Around 1299 CE, the Oghuz Turkish leader Osman established an independent beylik rule around Söğüt on the edge of Bithynia in northwestern Anatolia.

Timeline

1290–1298northwestern Anatolia · AnatoliaAfter the Mongol invasions the Sultanate of Rum existed in name only; Osman's father Ertuğrul's tribe settled in the borderlands, and after Osman inherited the chieftainship he gradually absorbed surrounding Turkic nomadic and semi-nomadic populations.
1299Söğüt · BithyniaOsman launched raids against the Byzantine frontier in the name of gazah (holy war) and captured strongholds such as Yenişehir, formally ruling around Söğüt as an independent bey; later tradition takes this year as the starting point of the Ottoman dynasty's chronology.

Encyclopaedia Britannica: Osman I https://www.britannica.com/biography/Osman-I
The Cambridge History of Turkey, Volume 1: Byzantium to Turkey, 1071–1453 — Kate Fleet (2009)