From Scandinavia: A History, by Ewan Butler (New Word City, 2016), Kindle pp. 16-17:
While the Danes and the Norwegians were venturing southward and westward in their search for a better life, the Swedes looked toward the East. Already, Swedish Ruotsi, or rowing men, had made themselves the masters of much of the eastern coast of the Baltic and had established settlements in what would later be called Finland, Estonia, Lithuania, and Latvia. But the Swedes were not content to remain on the Baltic coast. They rowed their longships down the gulf which leads to modern St. Petersburg and up to Lake Ladoga, that great inland sea. Thence, the Ruotsi, or “Rus” (as the Slav tribesmen they met corrupted the name), set the prows of their vessels toward the south, down the network of rivers that run to the Black and the Caspian seas. They were led, the Russian chroniclers tell us, by Rurik and two lieutenants, Askold and Dir, who were possibly his brothers. Rurik founded a “kingdom” south of Lake Ladoga and established the city of Novgorod, while his brothers, pressing farther south, set themselves up as kings of Kiev, on the Dnieper River. By the year 900, the two Swedish colonies were united as the lusty new state of Kievan Rus. Russia owes its name and its foundation as a nation to these Swedish oarsmen.
The purpose of the Swedes was not so much conquest, though that was an essential part of their plan, as trade. Swedish ships plied the river courses in such numbers that even Constantinople was threatened by the merchant-marauders. There, at the seat of the Roman Empire, the Swedes gathered goods from the East – gold, silver, carpets, tapestries, perfumes, leatherwork, dried fruits, precious stones, and many other things never before seen in their homeland. These treasures were shipped to Gotland, a large island in the middle of the southern Baltic Sea, which developed into a rich trading entrepôt. To it came merchants from the mainland of Sweden, Denmark, and countries as far afield as France and Holland. Modern research has unearthed in Gotland hoards of coins from every part of the world known to tenth-century Europe.