As I am in Austria (even though I'm a heretic Protestant North German), I went with Wallenstein, general of the Holy Roman Empire against the League in the Thirty Years War. Fittingly, my character is named John (Johannes) Tilly, another general from that era.
My character is Irish (as am I in real life) - The Morrigan is a Diety from Celtic Mythology. She is associated with sovereignty, prophecy, war, and death on the battlefield. I thought it was appropriate.