Marines in the Civil War

From Wikipedia.

The United States Marines were generally relegated to a minor role during the Civil War, most of their duty being on blockade duty.  As more and more Southern states seceded, the Corps lost a third of its officers who started the Confederate States Marine Corps.

A Marine company performed poorly at the First Battle of Bull Run and retreated along with the rest of the Union Army.

Blockade duty included sea-based amphibious landings.

In late November 1861 a group of Marines and sailors from the USS Flag landed in force at Tybee Island, Georgia and occupied the Lighthouse and Martello Tower at the northern end of the island.  It would later be an Army base for the bombardment of Fort Pulaski.

--Old SecMarine