Private Marcus Olivieri was born at Genoa, Ligura, Italy on November 25th, 1835.
In 1860, he was living at Key West, Florida and employed as an assistant at the Marine Hospital.
He was mustered into service on December 1st, 1861 as seaman with Captain Henry Mulrenan’s Florida Volunteer Coast Guards; on January 9th, 1862 he was assigned to the crew of the Mollie Post.
He remained in this unit mustered into Confederate service on April 25th, 1862 when he was enlisted as a Private in Captain Smith’s Company (Key West Avengers), 7th Regiment Florida Infantry by Major R. B. Thomas at Tampa, Florida for a period of 3 years or the war.
He was discharged October 30th, 1862 at Knoxville, Tennessee under Surgeon’s Certificate. At the time of his discharge, his physical description is given as 5’ 11” tall, dark complexion, dark eyes and black hair. Occupation given as “merchant”.
He is reported to have been engaged in blockade running after his return to Key West.
He died at Key West, Monroe County, Florida on October 5th, 1887.