Answer:
West Texas is very desolate and dry, which made it very difficult to farm there, so not many people settled in the 1700-1800s. East and South Texas are much more humid and green, and this made it easy to farm. Many people settled there in the 1700-1800s, and these communities eventually grew into major cities today, like Dallas, Fort Worth, Austin, San Antonio, and Houston.
Hope this helps!