Восточные славяне
At the end of the nineteenth century, many East Slavs immigrated to North America. They were Christians, some of them belonging to Eastern Orthodoxy, while others were Eastern Catholics of the Byzantine Rite. In Catholic terminology, East-Slavic form of the Byantine Rite was known as the "Ruthenian Rite", and thus the same "Ruthenian" designation was applied to East Slavs of that rite.