When Texas entered the union, because she was a nation, she retained all her lands. Federal lands in Texas are from modern times and there is not a lot of federal land in Texas
Big Bend was originally a state park(100,000 acres) but Texas gave it to the feds in the 1940s. Big Bend Natl Park was greatly expanded by the feds buying additional lands to make it larger.
Sometime along the way Big Bend was given a UNESCO designation and Texas didn't like that. Then the Rotary Club International started promoting Big Bend as a Peace Park with Mexico, and Texas didn't like that.
Big Bend Ranch came up for sale in the 80s. It was quite large and adjoined Big Bend Natl Park. Texas didn't want the Park Service to buy this ranch, so Texas bought it and it has been a financial liability to Texas Parks and Wildlife ever since.
Thanks for this information!
Texans are glad this is a state park. The rangers are WAY more user friendly and less adversarial than the national park rangers. The rules are looser. You are free to go off the trail and poke around there, which is cool, because there is lots to see and do.
Plus, the state park allows mountain biking - there are many many miles of single track to explore, and one of the trails is listed as "best in North America" by IMBA, the international mountain biking association.
But Big Bend National Park? They will ticket and fine a bicyclist the moment he leaves the pavement. There are no bikes allowed on any trails. The park police are hateful and militant. They suck.