Frank Frantz (May 7, 1872 – March 9, 1941) was an American Rough Rider and politician who served as the seventh and final governor of Oklahoma Territory (1906–07).

[1] Frantz ran on the Republican ticket to serve as the first Governor of the State of Oklahoma, but lost the election to Democrat Charles N. Haskell.

On May 1, 1898, at the age of 26, Frantz enlisted in the 1st United States Volunteer Cavalry, which the American press called the Rough Riders.

Upon joining the Rough Riders, Frantz returned to Indian Territory and met the regiment's charismatic second-in-command, Lieutenant Colonel Theodore Roosevelt.

After joining the Rough Riders, Frantz was assigned to A Company and given the rank of First Lieutenant, where he served as the Deputy Commander under Captain William "Bucky" O'Neill.

Traveling to Daiquirí, Cuba, the Rough Riders would engage, on June 24, 1898, in the Battle of Las Guasimas, the first clash between American and Spanish forces.

On June 30, Colonel Leonard Wood, the commander of the Rough Riders, was promoted to the rank of brigadier general.

Frantz immediately took over the command and led the company to a successful charge up Kettle and San Juan Hills.

In the coming months, on December 10, 1898, with the Treaty of Paris, Spain ceded the Philippines, Guam, and Puerto Rico to the United States and Cuba gained its independence.

However, for reasons that are unknown, it would take a full five years since the month he was initiated to earn the degree of Master Mason (a full-fledged member of Freemasonry) on June 12, 1905.

On his visits to the White House, Frantz, an athlete and a boxer, engaged in several matches with Roosevelt, knocking him out on three occasions.

[1] Frantz would serve in this post for another two years, when Roosevelt appointed him Indian Agent of the Osage Agency at Pawhuska.

Immediately upon coming into office, Governor Frantz discovered that oil companies were drilling on land reserved for public buildings after statehood in Pawnee County without obtaining permission.

Frantz made an unsuccessful attempt to reenter politics, running to serve as the Congressman representing Oklahoma's First Congressional District in 1932.