Some observations on the image and manuscript
and its usefulness in interpreting kit:
1) The particular image depicts Mongols "Batu's Tatars conquered the Ugrians, and took Menush ...and brought him to Batu" Not Russians. So, if any results could be drawn from the images, this would not be the right one for you to look at.
2) From an artistic point of view, I find this manuscript amazing as it uses a very strong Persian-Mongol book illustration framework while integrating it with very Byzantine-Russian detail.
3) From an armour point of view, and especialy from the point of view of trying to figure out what folks were wearing 300 years before the art was done, I believe this document is largely useless. The artist did not know (and largely did not care) what the folks 300 years ago looked like -- except as to how they fit into his iconographic tradition.
4) looking at the rest of the work, it is evident that the artist was not particularly interested in showing armour and did so in such a schematic fashion that any interpretation would have to be based on knowledge completely external to the manuscript.
4) If you are going to artistic sources for Alexander Nevsky, you'd be more likely to be accurate if you enjoy Eizenshtein's movie "Alexander Nevsky" - it is quite available in the US and the clothing and armour is presented in quite strong detail (though often at least modestly out of date).
5) If you realy want guesses on the clothing in the manuscript and specificaly the picture you presented, compare (for instance) this picture.
http://www.goldschp.net/SIG/nevskii/nev65.jpg Note that he yellow bands with circles appear at the collar, cuffs, and bicep band of the non-armour clothing. Consistant with some of the much later icons presented above, this is most likely decoration. This is also consistant with saying -- these guys are wearing Brigandines/Coats of Plate as found on a number of coins contemporary with Nevsky (on which the nails are visible but fabric decoration is not shown).
A fairly good likelyhood of an accurate mid 13th century Russian (or Polovtsian) portrayal is a Coat of PLates with Pteruges at the upper arm and waist over a knee length shirt (it is probably a linen front opening coat).
The Polovtsian (Kipchak) Babas (statues) do show a "bra" sort of armour (and at least one has been found) -- one disk at the back, two disks in front (a little above the chest actualy) all connected with a belt under the arm and belts over the shoulders. But I don't think that this is shown in this piece of art)
If you go to my site as it is presented at
www.archive.org (use the "wayback machine" to find
www.geocities.com/normlaw ), look up the article "mirror and brasier armour"
