Draft:Battle of Mount Armenia

The Kayı Tribe lived in the Söğüt and Domaniç regions, which were under the rule of Ertuğrul Gazi. During this period, very good relations were established especially with the Tekfur of Bilecik. After the death of Ertuğrul Gazi in 1281, this good relationship continued during the reign of Osman Gazi, who became the chief of the Kayı tribe. The Kayı people lived in Söğüt in winter and Domaniç in summer. On their way from Söğüt to Domaniç in the summer, they entrusted their valuable and heavy belongings to the Tekfur of Bilecik. According to the agreement, these items were left by women and unarmed youths. In return, Tekfur was to be given gifts. During this journey, the Tekfur of İnegöl, who was hostile to the Kayı tribe, was blocking the road and damaging the belongings and animals of the people. In fact, he was provoking other Tekfurs against Osman Gazi.

When Osman Bey became the leader of the Kayı Tribe, he first went on an inspection trip in 1284 with about 120 cavalry in the geography of Mount Ahî, which is located in the north of the İnegöl Plain and was known as "Cebel-i Ermeniyye" in those years. The Tekfur of İnegöl, Nikola, who heard about this inspection trip to be made by Osman Bey, set up an ambush for him around the Delikli Kaya in today's Hamzabey Strait, which is called "Ermeni-Beli" in Ottoman sources. During the first clash in the region to escape the ambush, Osman Bey's nephew and son of his brother Savcı Bey, Bayhoça, died. The Kayı army, which broke through the enemy circle with a successful attack, escaped from there, leaving the enemy alone with its own dead and wounded.^{[1][failed verification]}

After the Mount Armenian raid and the death of Bayhoça, Samsa Çavus requested Osman Bey to allocate the Kara-Tekin Castle, located near Bakaçak Hill, in order to put Nikola, the tekfur of İnegöl, in his a difficult situation and neutralize him, but Osman Bey did not accept this offer made by Samsa Çavus in accordance with the strategy he determined. The Byzantine army, on the other hand, could not get any results from the battle. The Mount Armenian raid and Bayhoça's death were the first steps taken on the way to the conquest of İnegöl. This war was the first war of the Ottoman Empire before its establishment^[2] and acted as a prelude to the Siege of Kulaca Hisar.

• Kayı Tribe
• Siege of Kulaca Hisar
• Conquest of İnegöl