Antique Cast Iron Picture

Here is a piece of Cast iron art which I do believe dates back to the 16th or 17th century, but that is only a guess. It does show that the picture is of war times , with all the canons, knights , and even a woman cutting a mans head of  In one hand she is holding his head in the other a sword. The detail is absolutely amazing. Somebody spent a lot of time carving this piece out, onto a template before being cast. The pictures just do not do this any justice at all. There is also a line of writing , but it is in Latin which I never learned when I went to school.. I have never seen anything like it anywhere. Could someone please tell me what it actually is and how much it is worth?