There is some more information on the web about Koenig and Baker.

Koenig appears to have been the composer of the well known Post Horn Gallop which is in the repertoire of quite a few brass bands and has been recorded once or twice since 1896.

Baker (assuming he is the same one) is quite a prolific American arranger of music.

I can't find any personal details of Koenig on the web, like birth and death dates.