There were times, in the summer of 1861, when it seemed as if the Confederacy would succeed in greatly extending its reach westward. As early as June, there were Texans crossing into the New Mexico Territory, and by August they raised Confederate flags over Flagstaff, Arizona. This operation was undertaken with the slenderest of means, but for once, the Union could be said to experience the same difficulty.

Jefferson Davis and his Cabinet were keen on expanding to the New Mexico Territory, but they neglected something closer to hand: the state of Missouri. Ever since a small federal force kept the federal arsenal at St. Louis, the North had the upper hand. But former Governor Claiborne Jackson and Texas Ranger Ben McCulloch put together an army of about 11,000 and reclaimed the western part of Missouri. Their big clash with the Federals took place at Wilson’s Creek on August 10, 1861.