Kievan Rus' was an early medieval East Slavic state covering much of eastern Europe. It is considered to be the cultural ancestor of modern-day Russland, as well as contributing much to Lithuania and Crimea. The north broke away in 1236 under the leadership of Novgorod, while the south started to disintegrate as the old trade routes from the Varangians to the Greeks dwindled in importance. In 1240 the state finally collapsed under the pressure of the Mongol conquests, fragmenting it into many successor principalities paying tribute to the Golden Horde.