Sam Houston was an interesting man, Governor of two states, president of a young republic, a general (and talented one at that), a slaveholder yes, but he considered the civil war an effort in futility.
He was strongly opposed to Texas secession and gave one of his most famous speeches in opposition to it.
For anyone interested, T. R. Fehrenbach's "Lone Star" is a great history of Texas and of Sam Houston (among many other colorful characters).