Johnny Clem - He enlisted at the age of 10, served in the 22nd Regiment Michigan Infantry as a drummer boy. In 1863, he was promoted to Sergeant after shooting a Confederate officer at Chickamauga. He is the still considered to be the youngest non-commissioned officer in United States history.
"I can not imagine what this man is thinking" (Image from Congo Free State under Leopold II - A father stares at the hands of his five year-old daughter, which were severed as a punishment for having harvested too little caoutchouc/rubber)
Albert Henry Woolson (February 11, 1848 – August 2, 1956) was the last surviving member of the Union Army, which fought in the American Civil War. He was also the last surviving Civil War veteran on either side whose status is undisputed. At least three men who followed him in death claimed to be Confederate veterans, but their status as Civil War veterans has been debunked.
Carl Maxie Brashear (January 19, 1931 – July 25, 2006) was the 1st African American to become a U.S. Navy Master Diver, rising to the position in 1970. His life story is dramatized in the 2000 motion picture Men of Honor, in which he was portrayed by actor Cuba Gooding, Jr. Brashear enlisted in the U.S. Navy on Feb 25, 1948, shortly after the Navy had been desegregated by President Truman. He graduated from the U.S. Navy Diving & Salvage School 1954-1st African-American to attend & graduate.