Islam in Turkey dates back many centuries. The region comprising modern Turkey has a long and rich Islamic tradition stretching back to the dawn of the Seljuk period and Ottoman Empire. The country has many historical mosques present throughout the cities and towns, including many in Istanbul.
Turkey is a secular state. Islam is the main religion of Turkish people, and is the largest religion in the country. Statistics show that 98% of Turkish people are Muslim, with 70% of these being Sunni.
The secularization of Turkey started in the society during the last years of Ottoman Empire and it was the most prominent and most controversial feature of Mustafa Kemal Atatürk's reforms. Under his leadership, the caliphate—the supreme politico-religious office of Islam, and symbol of the sultan's claim to world leadership of all Muslims—was abolished. The secular power of the religious authorities and functionaries was reduced and eventually eliminated. The religious foundations were nationalized, and religious education was restricted and for a time prohibited. The influential and popular mystical orders of the dervish brotherhoods (tarika) also were suppressed.
Turkey's largest mosque is the Sultan Ahmed Mosque in Istanbul. It is famously called the Blue mosque and has 6 miranets.
In Turkey, the wearing of a hijab is banned in universities and public buildings – this includes libraries or government buildings. The ban was first in place during the 1980 military coup, but the law was strengthened more in 1997. Over the years thousands of women have been arrested or prosecuted for refusing to take off the hijab or protesting against the ban, by the secular institution. There has been an increase in the number of people who wear the hijab particularly in Ankara and Istanbul.
There has been some unofficial relaxation of the ban under governments led by the conservative party AKP in recent years, for example the current government of the AKP is willing to lift the ban in universities, however the new law was upheld by the constitutional court, and on the other hand the Turkish military sees itself as the protector of secularism. The ban has been highly controversial since its implementation, in a country where 99% are either practicing or nominal Muslims or assumed as Muslim by the state. About 11% of Turkish women wear the hijab, although more women wear a cultural headscarf that isn't a symbol of the Qu'ran.
In cities like Istanbul and Ankara most women do not cover their heads. In some cities in eastern Turkey where the AKP has much support more of the women cover their heads.
In February, 2008, the Turkish Parliament passed an amendment to the constitution, allowing women to wear the headscarf in Turkish universities, arguing that many women would not seek an education if they could not wear the hijab. The decision was met with powerful opposition and protests from secularists. On June 5, 2008, the Constitutional Court of Turkey reinstated the ban on constitutional grounds of the secularity of the state. Headscarves had become a focal point of the conflict between the ruling Justice and Development Party (AKP) and the secularist establishment, which includes the courts, universities, and army. The ruling was widely seen as a victory for Turks who claim this maintains Turkey's separation of state and religion.