The series focuses on the life of Osman Bey, the son of Ertugrul Gazi and the founder of the Ottoman Empire. Osman begins his journey by forming a friendship with Yorgopolos and the Kayi tribe expands its influence further during the reign of Osman Ghazi, but some problems hinder Osman and he must solve it.
Osman faces many enemies and traitors in his quest and overcomes the obstacles. Osman also marries his love, Bala, amid his reign. He fulfills his missions with the help of his loyal companions, family, and friends.
The people of Anatolia was forced to live under the circumstances of the danger caused by the presence of Byzantine empire while suffering from Mongolian invasion. Kayı tribe is a frontiersman that remains its' presence at Söğüt. Because of where the tribe is located to face the Byzantine danger, they are in a continuous state of red alert. Giving the conditions and the sickness of Ertuğrul Ghazi, there occured a power vacuum. The power struggle caused by this war of principality is between Osman who is heroic and brave is the youngest child of Ertuğrul Ghazi and the uncle of Osman; Dündar and Gündüz who is good at statesmanship. Osman will fight internally and externally, both for the sake of Kayı tribe's future and for to rejoin with Bala Hanım by overcoming the obstacles they faced.