Between 1806 and 1812, over 370 men from the Saint Charles District of the Louisiana Territory were called upon to protect the settlers. Some served in the Boone’s Rangers, also known as the Mounted Rangers, and some served under James Callaway, which he called Minute Men in his log book.
The link below brings up a Printable PDF of a list of over 200 names. If I knew what Regiment(s) they were enlisted in, I noted it. Some on the list are veterans of the War of 1812 and may have served while still living in another State, but settled here, and later died and their headstone has been marked. It would be wonderful if every veteran of the War of 1812 could be marked. At the Saint Charles County Historical Society, they are happy to help you find out more information about your veteran.