title: Rough Riders
context: The Rough Riders was a nickname given to the 1st United States Volunteer Cavalry, one of three such regiments raised in 1898 for the Spanish–American War and the only one to see action. The United States Army was small and understaffed in comparison to its status during the American Civil War roughly thirty years prior. As a measure towards rectifying this situation President William McKinley called upon 125,000 volunteers to assist in the war efforts.[1] The regiment was also called "Wood's Weary Walkers" in honor of its first commander, Colonel Leonard Wood. This nickname served to acknowledge that despite being a cavalry unit they ended up fighting on foot as infantry.
question: How many served in the Rough Riders?
answers: 125,000