Kazakhstan
According to the 2009 Census data, there are very few Christians outside the Slavic and Germanic ethnic groups:
List of tribes and states in Belarus, Russia and Ukraine
The Slavs were a diverse group of tribal societies in the Iron Age and Migration Age Europe whose tribal organizations created the foundations for today's Slavic nations."See Slavicisation, Slavic peoples, East Slavs, West Slavs, South Slavs"
From the Mongol invasion of Rus' to the Battle of KulikovoAfter the Battle of KulikovoAfter the Great stand on the Ugra river