In the eyes of Texas and the whole South, the Hero of San Jacinto failed a loyalty test on Feb. 28, 1854 by voting against passage of the Kansas-Nebraska Bill.

Negotiations with the Plains tribes, which concluded in the summer of 1853, opened 13 million acres north and south of the Kansas River to immediate settlement. When Congress convened in December, legislation was introduced for organizing the vast new region.

By the time the bill reached the U.S. Senate, amendments had been added dividing t...