The nationality of Russia is Russian. The Russians are an East Slavic ethnic group indigenous to Eastern Europe, who share a common Russian ancestry, culture, and history. Russian, the most spoken Slavic language, is the shared mother tongue of the Russians; Orthodox Christianity has been their majority religion since the formation of a Russian identity in the Middle Ages. According to Advantour, more than 80% of the population of Russia are Russians, and the remaining percentage is made up of Tatars, Ukrainians, Chuvash, Belarusians, Mordovians, Germans, Chechens, Avars, Armenians, Jews, and others.