Legion of the United States - Wikipedia

One thing many people don't know - including many Marines - is that when the Legion of the United States was disbanded or converted to U.S. Army regiments, some of the unit's used uniforms were turned in and later taken out of supply stores and for issue to the newly re-raised U.S. Marine Corps in 1798. The Corps "new" uniforms consisted of dark blue coats with red "facings" (turn-backs on the lapels, cuffs and collar). The new United States Marine Band acquired former Legion musicians' uniforms of scarlet coats with dark blue facings. The Marines wore this uniform until sometime in the first decade of the 19th century, when a new uniform (again blue trimmed with red) was prescribed. The blue uniform trimmed with red is still with us in the form of the blue dress uniform, while the Marine Band carries on the tradition of the scarlet dress uniform. So, Marines, like many other things we have acquired or been issued over the years, our Corps' original uniform was a hand-me-down from the Army.

Excellent history share Tom.