To throw off his infantry rival, Wheeler left one regiment of his Cavalry Division, the 9th, at Siboney so that he could claim that his move north was only a limited reconnaissance if things went wrong. Roosevelt was promoted to colonel and took command of the regiment when Wood was put in command of the brigade. The Rough Riders had a short, minor skirmish known as the Battle of Las Guasimas; they fought their way through Spanish resistance and, together with the Regulars, forced the Spaniards to abandon their positions.[105]

Colonel Roosevelt and the Rough Riders after capturing Kettle Hill in Cuba in July 1898, along with members of the 3rd Volunteers and the regular Army black 10th Cavalry
Under Roosevelt's leadership, the Rough Riders became famous for the charge up Kettle Hill on July 1, 1898, while supporting the regulars. Roosevelt had the only horse, and rode back and forth between rifle pits at the forefront of the advance up Kettle Hill, an advance that he urged despite the absence of any orders from superiors. He was forced to walk up the last part of Kettle Hill because his horse had been entangled in barbed wire. 