Contacts between Russians and Persians have a long history, extending back more than a millennium. There were known commercial exchanges as early as the 8th century AD between Persia and Russia. They were interrupted by the Mongol invasions in the 13th and 14th centuries but started up again in the 15th century with the rise of the state of Muscovy. In the 9th–11th century AD, there were repetitive raiding parties undertaken by the Rus' between 864 and 1041 on the Caspian Sea shores of what are nowadays Iran, Azerbaijan, and Dagestan as part of the Caspian expeditions of the Rus'. Initially, the Rus' appeared in Serkland in the 9th century traveling as merchants along the Volga trade route, selling furs, honey, and slaves. The first small-scale raids took place in the late 9th and early 10th century. The Rus' undertook the first large-scale expedition in 913; having arrived on 500 ships, they pillaged the Gorgan region, in the territory of present-day Iran, and the areas of Gilan and Mazandaran, taking slaves and goods.