Henry Pleasants
Henry Clay Pleasants was a coal mining engineer and a brigadier general in the Union Army during the American Civil War. He is best known for organizing the building of an underground tunnel filled with explosives under the Confederate lines outside Petersburg, Virginia, resulting in the Battle of the Crater on July 30, 1864, an opportunity for Union troops to break the defense of Petersburg.
Pleasants was born in Buenos Aires, Argentina, and did not live in the United States until age 13, when he was sent to school in Philadelphia. He worked for the Pennsylvania Railroad and in anthracite coal mines. In 1857, he moved to Pottsville, Pennsylvania, to become a civil engineer in the local mining industry.
Source: Wikipedia