Shelby's "Iron Brigade" was a Confederate cavalry brigade in the Trans-Mississippi Theater of the American Civil War. The name was created by Joseph O. Shelby's former adjutant John Newman Edwards in his 1867 account, Shelby and His Men. In the autumn of 1864, some 1,500 of Shelby’s Iron Brigade cavalry surrounded Sedalia, Missouri, and overpowered local Union militia defenders. They began to loot and sack the town on October 15, 1864. Once General Thompson arrived in Sedalia, he ordered his men to stop the destruction, and moved them on, leaving Sedalia once again in Union hands.