Sudan (Arabic: السودان, as-Sūdān), officially the Republic of the Sudan (Arabic: جمهورية السودان, Jumhūrīyat as-Sūdān), sometimes called North Sudan, is an Arab state in North Africa (It is also considered to be part of the Middle East). It is bordered by Egypt to the north, the Red Sea to the northeast, Eritrea and Ethiopia to the east, South Sudan to the south, the Central African Republic to the southwest, Chad to the west, and Libya to the northwest. The population of Sudan is a combination of indigenous inhabitants of Nile Valley, and descendants of migrants from the Arabian Peninsula. Due to the process of Arabisation common throughout the rest of the Arab World, today Arab culture predominates in Sudan. The overwhelming majority of the population of Sudan adheres to Islam. The Nile divides the country into eastern and western halves.