The Rough Riders was a nickname given to the 1st United States Army Volunteer Cavalry, one of three such regiments raised in 1898 for the Spanish–American War and the only one of the three 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.
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.
Wood’s second in command was former Assistant Secretary of the Navy, Theodore Roosevelt, a man who had pushed for American involvement in the Cuban War of Independence. When Colonel Wood became commander of the 2nd Cavalry Brigade, the Rough Riders then became “Roosevelt’s Rough Riders.” That term was familiar in 1898, from Buffalo Bill who called his famous western show “Buffalo Bill’s Wild West and Congress of Rough Riders of the World.” The Rough Riders were mostly made of college athletes, cowboys, ranchers, miners, and other outdoorsmen. With these men being from southwestern ranch country, they were quite skilled in horsemanship.
The Rough Riders would go on to become heroes and Legends in the Battle of San Juan Hill, led by their Captain, and former Mayor of Prescott, William “Bucky” O’Neil. To learn more about the Rough Riders or Bucky O’Neil check out these links:
Rough Riders https://en.wikipedia.org/wiki/Rough_Riders
William Owen “Buckey” O’Neill (February 2, 1860 – July 1, 1898) was a sheriff, newspaper editor, miner, politician, Georgist, gambler and lawyer, mainly in Arizona. His nickname came from his tendency to “buck the tiger” (play contrary to the odds) at faro or other card games. He later became a captain in Theodore Roosevelt’s Rough Riders, and died in battle.
The Bucky O’Neill Monument, also known as the Rough Rider Monument, is an equestrian sculpture of Buckey O’Neill by Solon Borglum. It is located at Courthouse Plaza, Prescott, Arizona. It was dedicated on July 3, 1907 and was rededicated on June 6, 1982, and again on July 3, 1998. 
The inscription reads: (Signature lower proper left side of sculpture) (On relief plaque, back of granite boulder:)
Solon Borglum (On plaque, east side of granite boulder:)
ERECTED BY ARIZONA IN HONOR OF THE 1ST. U.S. VOLUNTEER CAVALRY, KNOWN TO HISTORY AS ROOSEVELT’S ROUGH RIDERS, AND IN MEMORY OF CAPTAIN WILLIAM O. O’NEILL AND HIS COMRADES WHO DIED WHILE SERVING THEIR COUNTRY IN THE WAR WITH SPAIN
(On plaque, front of granite boulder:) UNVEILED JULY 3RD 1907
SOLON HANNIBAL BORGLUM
AMERICA’S FIRST COWBOY SCULPTOR
THIS FREE-SPIRITED SON OF THE WEST, SENSITIVE TO THE CHANGING ERA IN WHICH HE LIVED, PORTRAYED THE WESTERN EPIC IN MARBLE AND BRONZE. OUR “BUCKY O’NEILL” MONUMENTAL BRONZE IS AMONG HIS GREATEST WORKS, AND IS ACCLAIMED BY THE CRITICS AS ONE OF THE FINEST EQUESTRIAN MONUMENTS IN THE WORLD.
PLAQUE DEDICATED JUNE 6, 1982, PRESCOTT COMMUNITY ART TRUST
“Bucky” The U.S. Army Rough Rider 100 Champion’s Troph
|Located on the Gurley St. side of the Courthouse Plaza in Prescott, AZ • “Erected by Arizona in honor of the 1st U.S. Volunteer Cavalry. Known to history as Roosevelt’s Rough Riders and in memory of Captain William O’Neill and his comrades who died while serving their country in the War with Spain.” “This free-spirited Son of the West, sensitive to the changing era in which he lived, portrayed the western epic in marble and bronze. Our “Bucky O’Neill” monumental bronze is among his greatest works, and is acclaimed by art critics as one of the finest equestrian monuments in the world.” The Bucky O’Neill sculpture by Jack Osmer is a replica of Solon Borglum’s statue. Solon Borglum was the brother of Gutzon Borglum who sculpted Mt. Rushmore in South Dakota. The statue was purchased by the city in 1907.