Muscovy (Grand Duchy) remained a fairly unknown society in Western Europe until Baron Sigismund von Herberstein published his Rerum Moscoviticarum Commentarii (literally Notes on Muscovite Affairs) in 1549. This provided a broad view of what had been a rarely visited and poorly reported state. In the 1630s, the Russian Tsardom was visited by Adam Olearius, whose lively and well-informed writings were soon translated into all the major languages of Europe.

Further information about Russia was circulated by English and Dutch merchants. One of them, Richard Chancellor, sailed to the White Sea in 1553 and continued overland to Moscow. Upon his return to England, the Muscovy Company was formed by himself, Sebastian Cabot, Sir Hugh Willoughby, and several London merchants. Ivan the Terrible used these merchants to exchange letters with Elizabeth I.

Despite the domestic turmoil of the 1530s and 1540s, Russia continued to wage wars and to expand. It grew from 2.8 to 5.4 million square kilometers from 1533 to 1584.[43] Ivan defeated and annexed the Khanate of Kazan on the middle Volga in 1552 and later the Astrakhan Khanate, where the Volga meets the Caspian Sea. These victories transformed Russia into a multiethnic and multiconfessional state, which it continues to be today. The tsar now controlled the entire Volga River and gained access to Central Asia.

Expanding to the northwest toward the Baltic Sea proved to be much more difficult. In 1558 Ivan invaded Livonia, eventually involving himself in a twenty-five-year war against the Polish–Lithuanian Commonwealth, Sweden, and Denmark. Despite occasional successes, Ivan's army was pushed back, and the nation failed to secure a coveted position on the Baltic Sea.

Hoping to make profit from Russia's concentration on Livonian affairs, Devlet I Giray of Crimea, accompanied by as many as 120,000 horsemen, repeatedly devastated the Moscow region, until the Battle of Molodi put a stop to such northward incursions. But for decades to come, the southern borderland was annually pillaged by the Nogai Horde and the Crimean Khanate, who took local inhabitants with them as slaves. Tens of thousands of soldiers protected the Great Abatis Belt — a burden for a state whose social and economic development was stagnating.