A Journey to Unsolved Mysteries By mymy_12 Oct 20, 1818 In War of 1818, the Treaty of Joint Occupation of Oregon was a result for that agreement and was renewed in 1827. Period: Oct 20, 1818 to Feb 14, 1859 Oregon Territory Feb 22, 1819 The Adams-Onis Treaty establishes the 42nd parallel as the southern boundary of the Oregon Country. February 22, 1819 Jun 15, 1846 Oregon Treaty peacefully designates the 49th parallel as the northern boundary of the United States. Oregon Treaty peacefully designates the 49th parallel as the northern boundary of the United States. Nov 29, 1847 A measles epidemic spreads among Indians of the Columbia Plateau; Whitman Massacre; Cayuse War Feb 2, 1848 The forthy-ninth parallel at the boundary of Oregon Country and the Treaty of Guadalupe Hidalgo brought future western states under the American flag. . Aug 14, 1848 Congress creates the Oregon Territory. Congress creates the Oregon Territory. Nov 4, 1854 The Congress made treaties whenever necessary with the Indians in the Oregon Territory Feb 14, 1859 Oregon becomes the 33rd state in the Union as a free state.
