I was recently offered some unpainted Napoleonics (mostly Russians) at a good price. My first thought was "opponents for Ian's mainstream DBN forces". My second thought was "where else were they employed?" A bit of research found the various scraps against the Ottomans, Persians & Georgians.
6 x [unknown] Cossacks (riders)
6 x Minifigs 11RC Cossack command
12 x Essex PNR19 Cuirassiers
2 x Essex PNR20 Cuirassier command (riders)
16 x Essex PNR17 Dragoons (riders)
6 x Essex PNR18 Dragoon command (riders)
12 x Minifigs 33RC Dragoons 1802 command
24 x Essex PNR4 Grenadiers
10 x Essex PNR5 Grenadier commands
19 x Essex PNR20 Hussar command (riders)
12 x Essex 29RC Hussars 1802 mirlitons
3 x Essex 32RC Hussars 1802 command
2 x [unknown] Hussars (one-piece castings)
8 x Essex PNR10 Jager firing
8 x Essex PNR11 Jager charging
6 x Essex PNR12 Jager command
7 x Essex PNR21 Lancer
2 x Essex PNR22 Lancer command
26 x Essex PNR6 Lifeguard
4 x [unknown] Lifeguard
15 x Essex PNR1 Line inf at ready
18 x Essex PNR2 Line inf firing
4 x Essex PNR3 Line command
29 x [unknown] Line inf marching, greatcoats
16 x Essex PNR26 Militia in greatcoat
1 x Minifigs 6THA Russian 6h team & driver, bicornes
17 x [unknown] artillery figures
5 x [unknown] artillery pieces
67 x 'loose' horses
6 x [unknown] Mounted Officers (one-piece castings)
I have not started work on the French who, at first glance, seem to be all guard infantry; or the Bavarians (less than 10 of them).
Stage 2 - Compare the DBN lists:
I can certainly make up any or all of the 3 'mainstream' sub-lists.
Stage 3 - What was different about the troops employed in the Caucasus regions?:
This will require some serious research...so here is my current reading list:
(1) Russo-Persian War 1804-13
(2) Russo-Turkish War 1806-12
(a) https://www.balkanhistory.org/russo-turkish-war-1806-12.html
(b) https://weaponsandwarfare.com/2016/01/14/russo-turkish-war-1806-1812/
(3) Russo-Turkish War 1811
(4) Russian-Turkish & Russian-Persian 1812
(5) Russian conquest of the Caucasus
This may take some time......