and North Carolina harbored also several tribes of Sioux,[265] who were also represented in southern Mississippi by the small Biloxi nation, though the chief Sioux area lay between the Arkansas and Saskatchewan rivers.  Similarly the Caddoes of Louisiana and eastern Texas had one remote offshoot on the Platte River and another, the Arikaras, on the upper Missouri near its great bend. [See map page 54.] But the territory of the Caddoes, in turn, was sprinkled with Choctaws, who belonged properly east of the Mississippi, but who in 1803 were found scattered in fixed villages or wandering groups near the Bayou Teche, on the Red River, the Washita, and the Arkansas.[266] Their villages were frequently interspersed with others of the Biloxi Sioux.

This fragmentary distribution appears in Africa among people in parallel stages of civilization.  Dr. Junker found it as a universal phenomenon in Central Africa along the watershed between the White Nile and the Welle-Congo.  Here the territory of the dominant Zandeh harbored a motley collection of shattered tribes, remnants of peoples, and intruding or refugee colonies from neighboring districts.[267] The few weak bonds between people and soil characterizing retarded races are insufficient to secure permanent residence in the face of a diminished game supply, as in the case of the Choctaws above cited, or of political disturbance or oppression, or merely the desire for greater independence, as in that of so many African tribes.

[Illustration:  DISTRIBUTION OF POPULATION IN THE UNITED STATES IN 1800.]

[Sidenote:  Ethnic islands of expansion.]

A scattered location results in all stages of civilization when an expanding or intruding people begins to appropriate the territory of a different race.  Any long continued infiltration, whether peaceful or aggressive, results in race islands or archipelagoes distributed through a sea of aborigines.  Semitic immigration from southern Arabia has in this way striped and polka-dotted the surface of Hamitic Abyssinia.[268] Groups of pure German stock are to-day scattered through the Baltic and Polish provinces of Russia.[269] [See map page 223.] In ancient times the advance guard of Teutonic migration crossed the Rhenish border of Gaul, selected choice sites here and there, after the manner of Ariovistus, and appeared as enclaves in the encompassing Gallic population.  While the Anahuac plateau of Mexico formed the center of the Aztec or Nahuatl group of Indians, outlying colonies of this stock occurred among the Maya people of the Tehuantepec region, and in Guatemala and Nicaragua.[270]