Cast and characters
Engin Altan Düzyatan as Ertuğrul Bey: Ertuğrul Bey, based on the historical figure of the same name, is the son of Süleyman Şah and Hayme Hatun, husband of Halime Hatun and İlbilge Hatun, and the father of Gündüz Alp, Savcı Bey and Osman Bey. After the death of his father, he leads a portion of the tribe to the western borders of the Sultanate of Rum and establishes himself as the Bey of his own Kayı tribe. He frequently battles against Templars, Mongols and Byzantines. Düzyatan was initially reluctant to accept the role, fearing the show would be "ridiculous". He read 13th century works such as the Book of Dede Korkut in preparation for the part. Düzyatan called Ertuğrul "a real hero", and "smart, mature and just", praising his "vision, strength, purpose in life and all of his values", comparing him to Batman and Spider-Man.
Kaan Taşaner as Gündoğdu Bey: Gündoğdu Bey, based on the historical figure of the same name, is the eldest son of Süleyman Şah and older half-brother of Ertuğrul. He is married to Selcan Hatun and has two sons. For the first season, Taşaner "preferred Gündoğdu to behave like [himself]". By February 2019, Taşaner was in negotiations to reprise the role for the fifth season.
Hülya Darcan as Hayme Hatun: Hayme Hatun, based on the historical figure of the same name, is the widow of Süleyman Şah and mother of Ertuğrul. Darcan "found some of [Hayme's] characteristics in [herself], such as her patience, love of children, and sense of justice and self-sacrifice", with co-star Hande Subaşı describing Darcan as "like a mother" to the other actors during filming. Commentators praised Hayme's characterization, with Darcan hoping Hayme would be an example for women.
Didem Balçın as Selcan Hatun: Selcan Hatun, loosely based on the Book of Dede Korkut character Princess Saljan, is the wife of Gündoğdu, elder sister of Gökçe Hatun and sister-in-law of Ertuğrul. Balçın felt that Selcan was "a respected woman" as "she left her individuality and thought of the whole", and that her depiction was "important in terms of showing the importance given to a woman." Balçın reprised the role in the sequel, Kuruluş: Osman.
Esra Bilgiç as Halime Hatun: Halime Hatun, based on the historical figure of the same name, is the first wife of Ertuğrul, the mother of his children, and the Hanım of the Kayı tribe. Bilgiç made her acting debut in the series, calling it "an unbelievable opportunity" for her. Bilgiç described Halime as "cool-headed", with comparisons made to Hürrem Sultan; Bilgiç felt there were differences between the pair. She practiced swordfighting for the role, and said her role was ended after the fourth season as "the story of the new season [was] changed".
Cengiz Coşkun as Turgut Alp: Turgut Alp, based on the historical figure of the same name, is an alp of Ertuğrul Bey. Coşkun said he was excited "to revive such an important historical character", visiting Turgut Alp's grave during filming for the second season. Coşkun trained for one year for the role, and was considered for five different roles before being cast as Turgut, saying that he joined the series as "there was no project describing the founding period of the Ottoman Empire" at the time. He characterized Turgut as "a person who solves problems [...] with his intelligence" rather than with weapons.
Nurettin Sönmez as Bamsı Beyrek: Bamsı Beyrek, based on the Book of Dede Korkut character of the same name, is an alp of Ertuğrul Bey. Sönmez did not appear in part of the second season due to a foot injury incurred in a motorcycle accident. Sönmez said he "focused on the [...] effects of the conditions and atmosphere of the period on people", and "set [his] heart on being Bamsı Beyrek." Sönmez called Bamsı "a duty man", saying he was "like a walking heart" and "very attached to his brothers [fellow alps]". Sönmez reprised the role in Kuruluş: Osman.
Hande Soral as İlbilge Hatun: İlbilge Hatun, loosely based on the historical figure El Bilga Khatun, is the daughter of Umur Bey of the Umuroğlu tribe and sister of Beybolat Bey and Sırma Hatun. She is the second wife of Ertuğrul Bey. With İlbilge taking Halime Hatun's role in the series, TRT 1 coordinator Kurtuluş Zaman said Ertuğrul "fall[s] in love with the sister of his worst enemy", adding her love with Ertuğrul was "as if [it was] the first season".
