Turkish nationality law

Turkish nationality law is based primarily on the principle of jus sanguinis. Children who are born to a Turkish mother or a Turkish father (in or out of marriage) are Turkish citizens from birth. The intention to renounce Turkish citizenship (or acquire citizenship from another state) is submitted in Turkey by a petition to the highest administrative official in the concerned person's place of residence, and when overseas to the Turkish consulate. Documents processed by these authorities are forwarded to the Ministry of Interior for appropriate action.

Citizenship is defined in Article 66 of the Turkish constitution:

A child adopted by a Turkish citizen automatically becomes a Turkish citizen if they are under 18 years old on the date the application for adoption was made. In some cases (although it is not required), those who have foreign names and are applying for Turkish citizenship change their name to a Turkish (but not necessarily a Muslim) name. Examples of people who have done this include football players Colin Kazim-Richards and Mehmet Aurélio.

Naturalization and loss of Turkish citizenship is controlled by the Vital Statistics Office (Turkish: Nüfus ve Vatandaşlık İşleri Genel Müdürlüğü), a department of the Ministry of the Interior.

Former Turkish citizens who were forced to give up their Turkish citizenship (for example, because they have naturalized in a country that usually does not permit dual citizenship, such as Germany or Austria) can apply for the Blue Card (Mavi Kart), which gives them some citizens' rights back, e.g. the right to live and work in Turkey, the right to possess land or the right to inherit. Excluded from this "Citizenship light" is the right to vote.

A foreign national may apply for nationalization if he or she meets all of the following conditions:

Meeting these conditions does not give a foreign national an absolute right to Turkish citizenship.

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Wikipedia