The Indian Territory, 1866-1906
IMMEDIATELY EAST of the Territory of Oklahoma lay the lands of the Five Civilized Tribes, which, together with the small reservations in the northeastern corner of the present state of Oklahoma, came to be known as the Indian Territory. By the close of the nineteenth century, the two were commonly referred to as the "Twin Territories." They were nearly equal in size, each having an area of approximately 35,000 square miles, but in most other respects they were very different. While the Territory of Oklahoma was composed largely of more or less level prairie plains, the Indian Territory was much more hilly and in certain parts distinctly mountainous, with considerable areas of wooded lands and, in the southeastern portion, extensive pine forests. The rainfall was also far heavier than in the western part of the Oklahoma Territory, and in consequence the vegetation was much more luxuriant. In addition, the Indian Territory had most of the coal and other mineral wealth, though after statehood extensive oil fields were also discovered in the area formerly included in the Territory of Oklahoma.
Population, government, and social and economic conditions were also very different in the two great regions. Both were essentially agricultural, but, in marked contrast to the Territory of Oklahoma, the population of the Indian Territory was for a long time made up largely of Indians living under their own tribal forms of government. Towns were very few and