Poitier was also the first black actor to win a prestigious international film award. With his unique career, Sidney Poitier helped change many stubborn racial attitudes that had persisted in this country for centuries. He has built the bridges and opened the doors for countless artists in succeeding generations.
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The U.S. claim was based on the explorations of Lewis and Clark and on the establishment of trading posts set up by John Jacob Astor's Pacific Fur Company, such as Astoria at the mouth of the Columbia River. Great Britain based its claim, in part, on James Cook's exploration of the Columbia River.
Explanation:
