Novgorod is one of the oldest Russian cities and was a major center of medieval Europe. According to ancient tradition, in 862, Rurik, the founder of the dynasty that ruled Kievan Rus, was invited by the inhabitants of the region to rule them. The city, whose name literally means "New City", was the cultural equal of Kiev. It obtained autonomy in 997 and achieved independence from Kiev in 1136, when it became the capital of the sovereign state known as Great Novgorod. This state included most of northern Russia west of the Urals. Situated on a major trade route between Scandanavia and the Baltic Sea to the Volga valley, it became a chief trade center of the Hanseatic League. Furs, hides, wax, honey, flax, and tar were the chief exports. Cloth and metals were imported from Europe and grain from the steppes of southern and central Russia. A great volume of trade also occurred with Central Asia. The citizens of Novgorod repelled the attacks of the Teutonic and Livonian Knights and of the Swedes. Novgorod escaped the Mongol invasions. It is the only region of Russia to have maintained an autonomous Orthodox Christian identity at a time when the rest of Russia was under the Mongol yoke. At its peak in the 14th century, the its population rose to an estimated 400,000. Its splendor during that period, with hundreds of churches and cathedrals built and decorated by the finest archictects, builders, craftsmen, and iconographers in Russia, its arsenals and armories, and its huge fairs featuring merchants and trade goods from much of the known world, have all furnished rich themes for Russian art, folklore, and literature.