Languages of the Ottoman Empire
The language of the court and government of the Ottoman Empire was Ottoman Turkish, but many other languages were in contemporary use in parts of the empire. Although the minorities of the Ottoman Empire were free to use their language amongst themselves, if they needed to communicate with the government they had to use Ottoman Turkish.
Linguistic imperialism
Anatolia was similarly diverse linguistically when it was ruled by small native states. Under the Persian and Hellenistic empires, the language of the conqueror served as the "lingua franca". The indigenous Anatolian languages disappeared.