Recently the importance of Texas in Western U.S. history became even clearer to me than before when I heard a presentation about the Pony Express. The speaker, Bert Schultz, said that Texas helped cause the creation of those fast-riding, young men with mail. Schultz grew up in Nebraska and lived near the actual route of the Pony Express.
A little background is needed. Texas broke away from Mexico in 1836, became a state in 1845, and then became a cause of the Mexican War from 1846 to 1848. When Mexico lost, it also lost the entire Southwest, including California. John Marshall discovered gold on the American River in Northern California about the time the Mexican War ended. Folks rushed to California for gold in 1849, and in 1850 California had enough people to qualify to become a state. (See how one thing leads to another!)