Wikipedia:Agios Nikolaos of Angelokomis

Agios Nikolaos (Turkish: Aya Nikola, Greek: Άγιος Νικόλαος) was the Tekfur of Angelokomis in the Byzantine Empire during the 13th or 14th century. His formidable foe was Osman Bey, the leader of the Oghuz's Kayı tribe. His defeat in the Battle of Mount Armenia, Siege of Kulaca Hisar and lastly, in the Battle of Domaniç, led to the rise of the Kayıs under Osman, who would later establish the Ottoman Empire.

In popular culture
He is portrayed by Erkan Avcı, in the famous Turkish historical drama Kuruluş: Osman.