Oklaho'ma, between Texas and Kansas, was organised in 1890 as a territory, and in 1906, absorbing the Indian Territory, became a state. In 1890 it consisted of two detached sections separated by the Cherokee Outlet, which, sold by the Indians in 1893, was then incorporated with the territory. The Public Land Strip situated N. of the Texas 'pan-handle' and S. of the parallel 37° N., ceded to the United States by Texas at its annexation, was not included in any state or territory until its incorporation in Oklahoma, and was known as No Man's Land. The area is 39,030 sq. m. Pop. (1890) 78,475; (1900) 398,331, including 18,831 negroes and 11,945 Indians. The surface, which rises gradually toward the north and west, is for the most part an upland prairie. The most important elevations are the Wichita Mountains in the south. Oklahoma is fairly well watered by the Red and Arkansas rivers and their affluents, but many of the streams are brackish, and so saturated with alkaline salts as to be at times unfit for drinking purposes or for irrigation. The rainfall is much lighter and also less uniform than in Indian Territory. In the river-valleys and in some of the upland regions there are fertile and productive spots. The Public Land Strip has an arid and unproductive soil covered here and there with a sparse growth of cactus, yucca, and sage-brush. The climate is subject to sudden changes produced by 'northers.' In 1886 the tribes to whom the lands of Indian Territory had been granted ceded the western portion of their domain to the United States. Notwithstanding the stipulation that it should be used only for settlement by other Indian tribes or freedmen, western speculators claimed that the lands were the property of the government, and open, like other public lands, for settlement under the Homestead laws. In 1879 an organised effort was made to take forcible possession of the lands, but the adventurers from Texas, Kansas, and Missouri were finally ejected by United States troops. After many difficulties from the renewed invasions of the 'boomers,' negotiations with the Indians were renewed, as a result of which, upon the receipt of an additional sum, the Indians waived all claims. This unoccupied area was opened for public settlement on April 22, 1889. No one was allowed to enter the borders until noon, but by twilight the population had increased by at least 50,000. Claims were selected, town sites staked out, and portable houses erected before nightfall. The territory was organised in 1890, and was, with the Indian Territory added, made a state in 1906. Chief centres of population are Oklahoma(ll,000), Guthrie (10,000), East Guthrie, and Kingfisher.