Clement Alexander Finley Flagler (August 17, 1867 – May 7, 1922) was a United States Army Major General who was noteworthy as regimental, brigade and division commander in World War I.

[4][5][6] He then accepted appointment to the United States Military Academy (USMA) at West Point, New York, after being recommended by Congressman Jerry Murphy.

While at West Point Flagler was nicknamed "Sioux" as a testament to his dark eyes, hair, and complexion, his having been raised in Iowa, and his self-professed Native American heritage, and his classmates used it with him for the rest of his life.

[13][14] During the Spanish–American War Flagler was temporarily promoted to major and assigned as engineer officer on the staff of the U.S. Army commander in Puerto Rico.

In December of that year the 7th Engineers was assigned to the 5th Division, then in its early stages of creation and commanded by Major General John E. McMahon.

[9] Having assumed command of the brigade on December 31, Flagler received another promotion, this time to the rank of brigadier general, on February 7, 1918.

[9] Upon its arrival in France, the brigade journeyed to Camp la Valdahon to receive instruction before rejoining the rest of the division in the St.

He was promoted again, this time to the rank of major general, on October 17, and continued to command the corps artillery until the Armistice with Germany on November 11, which brought an end to the war.

Eleven days later he received another assignment when he took command of the 42nd "Rainbow" Division, taking over from Brigadier General Douglas MacArthur.