Any ideas what this toile depicts?

This toile dates to about 1815-25 and was been engraved by Samuel Cholet who is well known for his sophisticated designs. I think this is a commemorative toile, but I have no idea what story or historical moment is depicted here. A military historian (thanks Sapper) who has helped me decipher many other designs is also stumped this this one. Please let me know if you have any ideas at all!