Now the word Rus' is really interesting. Most historians believe it to be the source of what we now say Russia or even Belarus, which means white Rus'. Some historians think it comes from the name of Sweden at the time. Some believe that the Rus' were a subgroup of Varangians, of Vikings. Some believe that the word is derived from those who row. But either way, the primary chronicle goes on to tell us, from 870 to 879, on his deathbed, Rurik bequeathed his realm to Oleg, who belonged to his kin and entrusted to Oleg's hands his son Igor, for he was very young. And then from 880 to 882, Oleg set himself up as prince in Kiev and declared that it should be the mother of Russian cities.