Was it a slavery and discrimination based on race or religion? You need to study history, really. It was an expansion case - something what many other countries did. Slavs conquested and captured Tatars, Udmurts, Yakuts, Eskimos and many others, but they did not make them their slaves or servants just because of those small ethical groups might look differently or have different religion. Slavs peacefully melted culturally and genetically with Tatars and many others and formed a big nation which we know nowdays as Russian. They all mostly remember their ethnical and cultural background, but consider themselves as mainly Russians. And only then, their other ethnicity. Like our beloved Elizaveta Tukhtqmysheva - a beautiful Russian Umdurt lady. "Friendship of people" by force - was a Russia's ethical strategy and internal politics for many centuries. As a result there were no slavery based on religion or race - everyone was Russian, not everyone is Slav - you know platinum blonde with blue eyes, but everyone is Russian. There were no second class citizens because of race or ethnicity in Russia, only the usual aristocrats-vassal-peasants type of society typical for those time all across the world back then. Btw, USA was not even on the map, when Russia and all Euors were shaping and melting their ethnicities in their sovereign nations. There were no cases like genocide of American natives tribes by colonialism of Euros. Russia's expansion certainly was by force like others, but later on they culturally assimilated and ethnically melted with all their new citizens (back in 12-19th centuries). It was a long process. They adopted a lot from other ethnical minorities. So current Russian culture is not Ruthenian, or Rus, or Slav culture. Russian culture is a melting pot. And it's very diverse, it's been like this for many centuries already. They did not put their "Russian Indians/natives" into slavery or reservations. Slavery was only a Euro colonization thing, not Russian. Slavs did not discriminate other new minorities because of religion or ethnicity, they accepted them and build one strong nation out of their diversity. USA and Russia are the only true multi-national and multi-cultural nations in the world right now. Canada is more like bi-cultural and successfully trying to be multi-cultural (but they are only at the beginning of this long and painful process).
Next time you want to bring something to my attention, bring something other than a Wikipedia article. *smiling politely*