My first thought was, "Duh, the Anglo-Saxon one," but the thing uses a 19 x 19 grid. I can get a 16" x 16" square out of my chamois, max. I was hoping for squares of at least an inch, which would seem to rule out alea whatsit, "the game of the evangelists."
Tablut was 9 x 9; the Welsh version, 11 x 11; the Irish, a petite 7 x 7. ...hm. If I make it a 9 x 9 board, one can play the 8 men on 16 version of tablut, or (by ignoring the outside rows and columns) the 4 on 8 Irish version. If I cut out a 12" x 12" square, that gives me 1.5" borders to decorate around the edges.
Decoration... I originally thought embroidery, but I do wonder if inks/dyes would be better. (Would probably be faster!) Well, I'll take some of the scrap from the chamois and try embroidering it and see how it goes. I have some cotton, some wool and even a bit of silk thread (and of course some... what is it? polyester? standard embroidery thread). Either way, I'll have to figure out how to transfer the ornamental design onto the chamois. Pricking? Carbon paper?