In the most detailed historical study of Islam under post-war Soviet communism yet published -- and the first to be based largely on official Soviet archival material available only since the demise of the Soviet Union -- Ro'i surveys all aspects of the Muslim faith that relate to the Soviet domestic scene. In the process, the author illuminates the often uneasy coexistence of government and religion, demonstrating how and why Islam survived in the face of Soviet authority. Ro'i begins with background on the dimensions of the Islam, as well as Soviet policy and legislation as it pertained to religion, before moving into investigations of both Establishment Islam -- the spiritual directorates, registered mosques and clergy -- and unofficial "parallel" Islam, which manifested itself in the form of unregistered groups and clergy. The author also considers Islamic practice and the observation of fasts, festivals, and rites of passage. Finally, the author turns his attention to the political realm, exploring regime policy as it relates to different religions as well as the religion's relationship with local organs of government.