Most of the songs are either taken directly from Youtube (like this British Grenadiers March), or from the movie Last of the Mohicans, like this.
You can try searching for the songs here, the playlist definitely has a ton of the songs from the mod.
Here's the French song that plays when you're in a tavern.
Here's the Spanish song that plays in taverns.
The song where a woman sings in some old Celtic tongue is this
The bagpipes & drums march that plays during some battles should be "Scottish Bagpipe & Drum Corps - Blue Bonnets / Bonnie Dundee / Campbells Are Coming". BUT, the exact video they took the thing from is unavailable. Here's the link. You can just find the three marches separately ("Blue Bonnets", also known as "Over the Border", "Bonnie Dundee" and "The Campbells are Coming"). I did found an Amazon link, though.
This is the song that plays when you travel through Spanish lands.
This is one of the bagpipe renditions of the LotM theme song which also appears in the mod.
Here's another one of the same kind.
All in all, the mod's had quite some musical influence from the Forty Five rebellion (or the Second Jacobite Uprising), which happened 10 years prior to the year the mod takes place in. The companion Michael, for instance, even states his family threw their lot in with the Jacobites, but since Bonnie Prince Charles Stuart lost the war and his father and brothers died, he fled to America to seek a better life.
Welp, that's as much as I could help with. A lot of the music is replaced with a 0:16 second long forest ambient. All in all, although I liked the feel, I kinda modded my own music into the mod at my own discretion. If you wish, I could share you the two music folders I have for the module (One that works very well for setting the theme when playing as a French/British character, and the other for a Native one).
Hope this helped!