
This map, from Texas Beyond History, a public education service of the Texas Archeological Research Laboratory (TARL) at the University of Texas at Austin, developed in collaboration with many other organizations, is useful in illustrating several aspects of Texas and American history.
The map illustrates Texas near the end of a very turbulent period.(1) A new nation was born in 1836 when it established its independence from Mexico. Mexico's refusal to recognize Texas as independent and Texian expansionism led to Texas invading Mexico in 1841 and 1843 and two Mexican attacks on Texas in 1842. The second Mexican invasion triggered the bizarre episode of the Texas Archive War. A bankrupt Texas entered the United States in 1845, while the outcome of the Mexican War (1846-48) established the state's southern boundary on the Rio Grande (Mexico claimed it was the Nueces). The Compromise of 1850 led to Texas relinquishing its claim to what is now New Mexico as far as the Rio Grande, which would have placed Santa Fe and Albuquerque in Texas. You can read more about this episode at When Texas Invaded New Mexico. Meanwhile, the failure of the 1848 revolution in Germany resulted in a large migration of free-thinking Germans to Texas where most settled in the Hill Country west of Austin.
Though Texas was the largest state in the Union, most of its territory was dominated by Indians; Comanche and, to a lesser extent, Apache. The map shows the end point of a couple of centuries of fighting among the tribes. The southern Great Plains had once been the home of the Navajo. They were driven westward across the Rio Grande by the Apache. In the early 1700s the Comanche (and their Kiowa allies) drifted south from Wyoming and pushed the Apache westward and southward.
It was the Comanche presence that caused newly independent Mexico to encourage Anglo settlement in Texas during the 1820s. Mexico, and its predecessor Spain, had difficulty encouraging settlements from the Hispanic population and turned to the Americans to help form a protective barrier from Comanche raids.
The new nation of Texas still struggled against the Comanche, with one Indian raid in the early 1840s even reaching the Gulf Coast near Corpus Christi. Along with its dire financial situation it was for protection from Mexico (which also briefly invaded Texas in the early 1840s, see Yo, Adrian) and from the Comanche that prompted the Texian agreement to enter the United States. The result was the construction of the line of forts by the US Army as indicated on the map.
In areas of Texas, settlement extended beyond the defense lines. This is a constant theme in American history. It is the settlers who proceed the government, not the other way around. In 1763 Britain attempted to establish a settlement line for its American colonies, but the effort failed as settlers moved on their own, in defiance of the government, into Kentucky and Tennessee. After American independence, the pattern continued with westward expansion, settlers always outpacing the areas under direct government control, provoking conflict with Indians and triggering military intervention to restore the peace and protect the settlers. You can read many military accounts from this era blaming settlers for most of the conflict.(2) This was at a time when the U.S. government had little presence in everyday life, outside of local post offices, and maintained a very small military; its capacity a fraction of what we have become accustomed to over the past century.
Comanche raids continued for another twenty years. In 2019 we visited the ancestral homestead of Lyndon Johnson in the Texas hill country and saw the home where LBJ's grandmother and aunt hid under the floorboards during an Indian raid around 1870.
And those German immigrants in the Hill Country proved to be Unionists in 1861, leading to years of violent conflict with the Confederate government of Texas.
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(1) Some would argue Texas has always been turbulent.
(2) In any event it is difficult to see how any long-term coexistence with the raiding, nomadic Comanche could succeed, in contrast with the tribes in the southeast who adopted American ways and were still expelled.