A photograph of the First United States Volunteer Cavalry, or “Rough Riders,” led by Theodore Roosevelt, circa 1860-1920.

The Rough Riders were the most famous volunteer regiment of the Spanish-American War. The regiment was led by Theodore Roosevelt, who, along with his men, achieved hero status in the American popular imagination as a result of their fighting, particularly after the Battle of San Juan Hill. Roosevelt is on the bottom row, third from the right.