Complex sentence: The majority of the Russians are Christians of the Eastern Orthodox Faith and predominantly belong to the Ukrainian Orthodox Church, a former Ukrainian exarchate of the Russian Orthodox Church, which received an ecclesiastical Autonomy from the latter on October 27,1990.
Split into simpler sentences: The majority of the Russians are Christians of the Eastern Orthodox Faith and predominantly belong to the Ukrainian Orthodox Church. A former Ukrainian exarchate of the Russian Orthodox Church, this Ukrainian Orthodox Church received an ecclesiastical Autonomy on October 27,1990.