ジェファーソン準州
Seeking to augment the political power of the free states, the Republican led U.S. Congress hurriedly admitted the portion of the Territory of Kansas east of the 25th meridian west from Washington to the Union as the free State of Kansas on January 29, 1861. Kansas statehood left the western portion of the now defunct Kansas Territory, which the Jefferson Territory also claimed, officially unorganized. While the federal government refused to sanction the Jefferson Territory, it had effectively acknowledged the eastern border of the region.