as Portuguese, is a prominent minority language in Ziguinchor, regional capital of the Casamance, spoken by local Portuguese creoles and immigrants from Guinea-Bissau. The local Cape Verdean community speak a similar Portuguese creole, Cape Verdean Creole, and standard Portuguese. Portuguese was introduced in Senegal's secondary education in 1961 in Dakar by the country's first president, Léopold Sédar Senghor. It is currently available in most of Senegal and in higher education. It is especially prevalent in Casamance as it relates with the local cultural identity. A variety of immigrant languages are spoken, such as Bambara (70,000), Mooré (37,000), Kabuverdiano (34,000), Krio (6,100), Vietnamese (2,500), and Portuguese (1,700), mostly in Dakar. While French is the sole official language, a rising Senegalese linguistic nationalist movement supports the integration of Wolof, the common vernacular language of the country, into the national constitution. Senegalese regions of Dakar, Diourbel, Fatick, Kaffrine, Kaolack, Kedougou, Kolda, Louga, Matam, Saint-Louis, Sedhiou, Tambacounda, Thies and Ziguinchor are members of the International Association of Francophone regions. Largest cities Dakar, the capital, is by far the largest city in Senegal, with over two million residents. The second most populous city is Touba, a de jure communaute rurale (rural community), with over half a million people. Religion Senegal is a secular state, although Islam is the predominant religion in the country, practiced by 96.6% of the country's population; the Christian community, at 3.3% of the population, is comprised mostly of Roman Catholics but there are also diverse Protestant denominations. Less than one percent has animist beliefs, particularly in the southeastern region of the country. Some Serer people follow the Serer religion. According to a 2012 Pew demographic study, 55% of the Muslims in Senegal are Sunni of the Maliki madhhab with Sufi influences, whilst 27% are non-denominational Muslims. Islamic communities in Senegal are generally organized around one of several Islamic Sufi orders called tariqas, headed by a khalif (xaliifa in Wolof, from Arabic khalīfa), who is usually a direct descendant of the group's founder; the study found that 92% of Senegalese Muslims belonged to a Sufi order. The two largest and most prominent Sufi tariqas in Senegal are the Tijaniyya, whose largest Senegalese sub-groups are based in the cities of Tivaouane and Kaolack and has broad following in West Africa outside of Senegal, and the Murīdiyya (Murid), who are based in the city of Touba and has a follower base mostly limited to