"In England during the time of the game period we had Matilda as Queen of England"

Empress Maude? The one that got disosseseed by Stephen of Blois and spent many years fighting back and forth with him and wound up losing? I think she ruled for all of one year, so her example, at least, tends to point to the contrary direction: a woman was unlikely to remain at the throne with so many ambitious nobles scattered about the landscapes.