Well, going by your chars history, which notes the wars beginning sometime after he was 1700... would put Kelvin at around 1046, give or take a few decades. (Assuming your description of events means that the wars began after that point.) Kelvin was a regular human before he died in the initial conflicts, however you want to use that to gauge.

If I was right though, it makes him a lot younger- though still closer in age than the majority of the other characters. I would guess that they would have crossed paths more than once in such a time period.