An estimate in 1824, recorded them at about 2,800, primarily living at the present-day site of Waco, Texas and on the east side of the Brazos River above the San Antonio Road. Afterwards, with the advent of the Austin colony, until the annexation of Texas by the United States, a period of about 25 years, their numbers constantly diminished in conflicts with the American settlers and with the raiding Osage from the north.

In 1835 the primary Wichita band, together with the Comanche, made their first treaty with the Government, by which they agreed to live in peace with the United States and with the Osage and the immigrant tribes lately removed to Indian Territory. In 1837 a similar treaty was negotiated with the Tawakoni, Kiowa, and Kiowa Apache. At this time, the Wichita had their main village behind the Wichita Mountains, on the North fork of Red River in Oklahoma. Later, they moved farther east and settled on the present site of Fort Sill, Oklahoma. In 1850, they moved still farther east to Rush Springs. In the meantime, the Tawakoni and Waco were ranging about the Brazos and Trinity Rivers in Texas.

In 1846, after the annexation of Texas, a general treaty of peace was made at Council Springs on the Brazos River with the main Wichita tribe, the Tawakoni, and Waco, together with the Comanche, Lipan, Caddo, and Kichai, by which all these acknowledged the jurisdiction of the United States. In 1855 the majority of the Tawakoni and Waco, together with a part of the Caddo and Tonkawa, were gathered on a reservation on Brazos River west of present-day Weatherford, Texas. However, due to the determined hostility of the Texans, the reservation was abandoned in 1859, and the Indians were removed to a temporary location on Washita River in Oklahoma. Just previous to the removal, the Tawakoni and Waco were officially reported to number 204 and 171 respectively. In the meantime, the Wichita had fled from the village at Rush Springs and taken refuge at Fort Arbuckle to escape the vengeance of the Comanche, who held them responsible for a recent attack upon themselves by United States troops under Major Van Dorn in 1858.

The Civil War brought about additional demoralization and suffering, most of the refugee Texas tribes, including the Wichita, taking refuge in Kansas until it was over. They returned in 1867, having lost heavily by disease and hardship, and were finally assigned a reservation on the north side of Washita River within what is now Caddo County, Oklahoma. In the next year they were officially reported at 572, besides 123 Kichai. In 1902 they were given allotments in severalty and the reservation was thrown open to settlement.

By 1906, the Wichita tribe numbered only about 310, besides about 30 of the confederated Kichai remnant, being less than one-tenth of their original number.