1.  Chad CIA Factbook
[By CIA THE WORLD FACTBOOK ]
Religions:
Muslim 53.1%, Catholic 20.1%, Protestant 14.2%, animist 7.3%, other 0.5%, unknown 1.7%, atheist 3.1% (1993 census)

Population:
10,975,648 (July 2012 est.)
country comparison to the world: 75

2.  President of Islamic Daawa and Relief Organization - Discourse
[by International Islamic News Agency(IINA)]

N’djamena, Rabi Thani 3/June 24 (IINA) - Dr. Haqqar Muhammad Ahmed, President of the Islamic Daawa and Relief Organization in Chad has said that Muslims constitute 85 percent of Chad’s population, more so after the Daawa activities that had taken place in the south of the country, and resulted in 37 bishops declaring their choice of Islam, followed by 800,000 others following in their footsteps. He said Christians make up five percent of the population, the rest being animists, most of them living in the south of the country, according to the 1962 statistics.

3.  Islam in Chad
[By WIKIPEDIA]
The earliest presence of Islam in Chad can be traced back to the legendary Uqba ibn Nafi, whose descendants can be found settled in the Lake Chad region to this day. By the time Arab migrants began arriving from the east in the fourteenth century in sizeable numbers, the creed was already well established. Instead of being the product of conquest or the imposition of political power, Islamization in Chad was gradual, the effect of the slow spread of Islamic civilization beyond its political frontiers.

4.  Demographics of Chad
[By WIKIPEDIA]
The people of Chad speak more than 100 different languages and divide themselves into many ethnic groups. However, language and ethnicity are not the same. Moreover, neither element can be tied to a particular physical type. In Chad, European conquest and administration intensified feelings of ethnic separateness by drawing local boundaries along perceived ethnic lines. The Europeans also appointed chiefs and other local African authorities who had little legitimacy over the groups they were to lead. In general, the French favored southerners over northerners and settled populations over nomads. This bias continued after independence and has been an important element in internecine conflict.