The mansion was built in the beginning of the 1900s as a private residence for
Kostaki Teophylaktos, a notable banker of
Greek origin. The architect of the mansion was Alexandros Kakoulidis, who was also the architect of the Greek College of Tebizond (Φροντιστήριον Τραπεζούντας), the Kapagiannidis villa, and other famous buildings in Trebizond. Teophylaktos went bankrupt in 1917 and all his properties were confiscated, among them his mansion. The building was acquired by the Nemlioğlu family. During the timespan of
Turkish War of Independence (1919–1923), the mansion was used as the headquarters for the military in the region. In 1924, it was prepared for the first visit of
Mustafa Kemal, the founder of the Turkish Republic, to Trabzon. Between September 15–17, he and the First Lady
Latife stayed in the mansion. In 1927, the building was nationalized by the Governor of Trabzon Ali Galip Bey, and served until 1931 as the Governor's House. Between 1931 and 1937, it was used as the inspector's office. The Kostaki Mansion was assigned in 1937 to the
Ministry of National Education, and was used for fifty years long as a vocational high school for girls. Finally, in 1987, the building was handed over to the
Ministry of Culture and Tourism to be transformed into a museum. == Museum ==