Born in St. Louis, Missouri, Paul was the grandson of René Auguste Chouteau.

He was wounded at the Battle of Cerro Gordo, but recovered to serve in the campaign to capture Mexico City.

He led a brigade as a brigadier general in 1st Division, I Corps during the Battle of Chancellorsville.

[1] His injuries left him totally blind and with severely impaired senses of hearing and smell.

Unable to perform anything except some administrative duties, he was kept on the Army's roll until February 1865, when he was officially retired from the service.