Here is a link to a page that has many different sets of flag codes.
It has both merchantmen codes and military codes. There are codes from the USN, RN, Soviet Union and the US civil war. There are also codes from the various systems developed by Lord Richard Howe, and by Sir Home Popham which is often noted as being first used in the famous Battle of Trafalgar involving Admiral Horatio Nelson.
Also shown are the flags of the Marryat code, which immediately preceded the current International Code of Signals with a couple of it's variations.
www.quadibloc.com/other/flaint.htm
I figure this one should about cover it 
,
J