The Slavic world spreads from Eastern Europe to the Pacific coast of Siberia. Around 280 million people have some variety of Slavic as their native language; about half are speakers of Russian. Slavic literary traditions date back to the 9th century CE, when Greek Orthodox missionaries Cyril and Methodius devised the first Slavic alphabet, now known as Glagolitic, for Old Church Slavic. Whil…