What are some good (but Forum safe) oaths or swears in French? I want something to draw on when things get heated in battle or the Council.

From reading some Harry Turtledove books about an alternate World War I I'm under the impression that Quebecois may swear by naming parts of a Church, ie "Tabernac!" Would this be applicable to medieval French (similar to the English "God's wounds") or am I off base?

Of course weren't there two main dialects of French in this time period?