Why did the Whitmans go to Oregon? How did their mission end?

The Whitmans, Methodist missionaries, offered religious instruction and medical services to the local Cayuse Indians. They also gave care and supplies to wagon parties travelling along the Oregon Trail. The Cayuse suspected that the Whitmans and their foreign religion were the cause of the fatal disease.

Whitman journeyed to Oregon to make a reconnaissance of potential mission sites; Because the Whitman's missionary efforts bore so little fruit, the American Missionary Board decided to close the mission in 1842 and transfer the Whitmans elsewhere.

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c) he felt the constitution clearly gave states this right.