The area was acquired by the United States through the Louisiana Purchase and became part of the new Arkansas Territory. On April 1, 1820, Arkansas created Miller County which included most of the land that would become Little Dixie. A post office at Miller Courthouse was established on September 7, 1824. Per a treaty signed on January 20, 1825, the land west of a line "one hundred paces east of Fort Smith, and running thence, due south, to Red river" was ceded to the Choctaw Indians. The residents west of the line made a futile attempt to be exempted from the treaty but failed. They burned the courthouse and most of the records before they left.