Asiatic Eskimos are the cultural and biological descendants of highly successful hunter-gatherers who for at least a couple of millennia had been well adapted to the Arctic ecosystem. First contacts with Europeans came during Russian explorations of the seventeenth century and later (such as that of V. J. Bering, who in 1728 "discovered" and named St. Lawrence Island), and navigators of other nationalities soon followed. The opening of the North Pacific whale fishery after the Middle of the nineteenth century brought many whaling ships, disease, new hunting equipment, and liquor into the lives of the Asiatic Eskimos. With the U.S. government's purchase of Alaska from Russia in 1867, a formal political boundary separated the St. Lawrence Islanders from their closest cultural relatives in Siberia, a boundary that was only infrequently observed until post-World War II animosities between the Soviet Union and the United States resulted in hostility sometimes and an "ice curtain" preventing centuries-old patterns of trade and intermarriage. In the late 1980s there occurred several friendship visits of Alaskans (including St. Lawrence Islanders) to the Siberian villages, where long-unseen relatives greeted each other and ties of common identity were renewed.