According to historical sources and archeological excavations, ancestors of modern Tatars - Bulgars - began to join Islam in the first decades of IX century, and this process was finished in 922 by declaration of Islam the official religion of Volga Bulgaria .
Islam became the major factor of Bulgars culture foundation and the integral component of their national consciousness.
Acceptance of Islam opened opportunities of familiarizing with Arabic-Muslim culture, penetration into Volga-Kama region of philosophical and literary art ideas of the East that played an essential role in development of culture and scientifically philosophical idea. With acceptance of Islam the certain system of education was adjusted, moral basics of public life were transformed. As well as any other religion, Islam comprises universal moral values, preaches the ideals of validity, love, humanity, moral perfection; condemns cruelty, violence, money-making.
From XIII Volga Bulgaria repeatedly experienced heavy shocks, from different borders was attacked by strangers; despite of it, people survived and kept their originality. The major cementing force in preservation of its unity, ethnic integrity was Islam.
After the conquest of Kazan by Ivan IV it became even worse. Despite of social and economic and national oppressions on the part of Russian empire, Tatar people kept the culture - in this a serious role Islam played.
Religious and national prosecutions on the part of the imperial government orthodox missionaries resulted in preservation of religious norms among Tatars-Muslims.
The Muslim Ulama ambiguously reacted on Bolsheviks revolution. The loyal attitude of Tatars to new authority explains partly by influence of Islamic movement inside the party of Bolsheviks which spokesman M.Sultan-Galiev was. He and some attendants of the cult tried to show the generality of ideas of the socialism, communism and Islamic doctrine.
After route of Sultan-Galiev's movement the attitude to Islam became irreconcilable. Cinemas, theatres, museums, clubs, libraries, periodicals - all was used as means of struggle against religion. Created in 1922 Tatar Communistic university trained atheists. The law demanding obligatory registration of religious associations practically cancelled the separation
of religion from the state proclaimed earlier.
The period of struggle coincided with collectivization and dispossession - Ulama - first of all, depriving of their civil rights. During mass reprisals of Muslims, besides general for all accusations, they were accused in a special way. "Enemies of people" were declared not only active opponents of transition from the Arabian writing on Latin (in 1928), and then Cyrillic (in 1939), but also those who stored books on Arabian diagram - even of secular contents. Many books were burnt, others the owners dug on cemeteries in tombs of ancestors. Till April, 1, 1939 from 1598 mosques and 560 churches working in the territory of the republic before the revolution, 817 were used for cultural establishments - schools, clubs etc., 159 - for economic needs.
But in the family life of Tatars, especially in the countryside, religious practices widely continued to be executed, frequently in parallel with new - Soviet ceremonies.
At the time of WWII the atheistic work was weakened and revival of religiousness became again. The clergy addressed to all believers with appeal of protection of Fatherland at the front line and in rear. In mosques they collected money, clothes, products for front and children's homes etc.
However in the second half of 50s the new period of bans began. Obviously: at the certain stage of development of ethnos, in conditions when national specificity of material life disappears, language is lost, history of people is forgotten, the religion plays a compensatory role in growing national consciousness. it carries out also guarding function, constraining its appearance of ethnic specificity, providing thus the survival of ethnos. During many centuries, owing to ability of Islam to the adaptation to local conditions and traditions and its regulation of all sides of life, close interpenetration of culture and life of people and religion took place. 47% of population in villages and 58% in Kazan consider it is impossible or hardly possible to keep national culture without religion. Among the Tatar art intelligence more than 80% think also this way.
From the end of 80s appreciable "thaw" in mutual relation of the Soviet state and the Muslim religious organizations was observed. Celebrations widely marked in the country on the occasion of 1100-anniversary acceptance of Islam in the East Europe and 200-anniversary of establishment of the Spiritual department of Muslims of the European part of the USSR and Siberia testify it.
Recently in Tatarstan, there has been a rough growth of religious communities and organizations; the quantity of mosques has increased in tens times, the higher Muslim educational institutions work. Two Spiritual departments function: one - as a branch of the Central spiritual department ( Ufa ), and the second - independent Spiritual department of Muslims of Tatarstan. Their functions are professional training of Ulama and their placement, participation in construction of mosques, realization of communications with other religious centers - including foreign, organization of pilgrimage to Makkah.