302 Native American policies in the United States and Canada diplomatic and political leverage of Native peoples in the Northeast Further west, a series of attacks launched by a Native alliance under the leadership of the Ottawa chieftain Pontiac in 1763 exposed Britain’s weaknesses west of the Allegheny and Ohio River valleys and in the Great Lakes region The unsettled conditions prompted the British government to issue the Proclamation of 1763, forbidding further settler expansion beyond the Appalachian Mountains Settlers largely ignored the proclamation, setting the stage for further conflict on the western frontier THE AMERICAN REVOLUTION A similar dynamic unfolded in the aftermath of the American Revolution The war split the Iroquois Confederacy, with the Mohawk, Seneca, and Cayuga allying with the British The victorious Americans retaliated, compelling large numbers of Iroquois to abandon their lands and migrate west or north to Canada In the South, the Cherokee and others took advantage of the fighting between the British and Americans to launch a series of attacks on frontier towns and settlements, prompting harsh retaliation after the war Overall, the Revolution severely weakened the position of Native peoples vis-à-vis the new American republic, while also opening Appalachia and the Ohio, Cumberland, and Tennessee River valleys to white settlement and, south of the Ohio, to the expansion of African slavery In the early republic, under the intellectual leadership of Thomas Jefferson in particular, U.S policy toward the Indian problem gelled into an eitheror proposition: either Indians east of the Mississippi River could assimilate into white society and become civilized, or they could migrate west of the Mississippi Either way, the U.S government would assume dominion of their lands As events unfolded, even eastern tribes’ adoption of all the hallmarks of civilization did not prevent the land seizures and forced migrations In the Old Northwest, the Treaty of Greenville of 1795 with the Shawnee, following the armed conflicts between the U.S Army and Shawnee in 1790–91, ceded most of present-day Ohio and parts of Indiana in exchange for the promise of a permanent boundary between Indian territory and the zone of white settlement, a pledge not enforced in subsequent years After 1815 with the 1812 U.S defeat of the coalition of tribes cobbled together by the Shawnee chieftain Tecumseh and defeat of the British in the War of 1812, the U.S government was in a position to enforce the Jeffersonian assimilate-or-migrate policy A series of Supreme Court rulings, beginning with Johnson v McIntosh (1823), provided constitutional backing for the policy, based mainly on the Indian commerce clause of the Constitution The rulings further defined Indian tribes as sovereign political entities subject only to the authority of the federal government and not state governments, largely resolving a key issue in the constitutional principle of federalism In 1824 the Indian Office was established under the administration of the War Department; in 1849 it became the Bureau of Indian Affairs under the authority of the Interior Department INDIAN REMOVAL AND DISPLACEMENT With the election of Andrew Jackson to the presidency in 1828, the U.S government embarked on an aggressive policy of Indian removal In 1830 Congress passed the Removal Act, which required Indian tribes east of the Mississippi to relinquish their ancestral lands and either become citizens of the states in which they resided or migrate west In the Northwest, the Sac and Fox under Black Hawk resisted and were defeated in the Black Hawk War of 1832 In the Southeast, the Five Civilized Tribes (Cherokee, Creek, Seminole, Chickasaw, and Choctaw) responded to white encroachment in a variety of ways, including armed resistance, the adoption of farming and Christianity, and the appropriation of nationalist discourses and practices In the 1820s a Cherokee nationalist movement under the leadership of John Ross and others, building on Sequoyah’s 1809–21 invention of an 85-character Cherokee syllabary, published the newspaper Cherokee Phoenix, the year after formally establishing a new nation-state in the Cherokee constitution of 1827, modeled on the U.S Constitution Under President Jackson, however, the pressures for Indian removal proved too great From 1830 to 1838 in the infamous Trail of Tears, upward of 30,000 members of the Five Civilized Tribes were forcibly removed and resettled in Oklahoma’s Indian Territory, a policy supported by the Supreme Court’s rulings in Cherokee Nation v Georgia (1831) and Worcester v Georgia (1832) By 1840 virtually all the lands east of the Mississippi River had been opened to white settlement, south of the Ohio River accompanied by African slavery WESTERN EXPANSION From the 1840s to the 1870s with the U.S victory in the Mexican-American War, the Homestead Act of 1862, the victory of the Union in the Civil War, the