Francis Asbury Vaughan left his home in Guadalupe County, Texas on July 4, 1862, to fight in the Civil War. But he did not join a Confederate unit. Unlike twenty-one of his brothers and cousins, and most white male Texans who fought in that conflict, he became a captain in the First Texas Cavalry, USA, the best-known Union outfit from the Lone Star State. Fortunately for historians, he recorded some of his wartime experiences in what he called a memorandum, which remains in the possession of his descendants along with other treasured records concerning him and his relatives. These documents are the foundation for this book, which provides a unique insight into the ideals and actions of a Texan who not only served for three years as a Union officer but afterward became a Republican for the remaining three decades of his life in Texas. As a Texan in blue, a delegate to the Constitutional Convention of 1868, a federal appointee and elected local official several times over, and a successful businessman and father, Vaughan established a legacy that offers useful perspectives not only on him, but on the events that surrounded and involved him.