I attempted to make King's Cake, but it didn't turn out too well (the frosting wasn't right at all.) Making King's Cake requires making Brioche, so I baked up the remaining batter as a loaf of bread. Brioche seems to be the same thing as the 18th century "French Bread" I have made many times from a recipe in (I think) English Housewifery. Now it makes sense why it was called that.
grayness:
I heard somewhere that Brioche was what Marie Antoinette was actually referring to in the infamous "Let them eat cake." remark.
aristophanes:
I have heard that too, about Antoinette. But, I've also heard that she never said that to begin with. (There's apparently some book of the era with a story of "a princess" making that remark, it's unclear whether or not it's really a true story at all, and probably wouldn't have been referring to Marie Antoinette at that point.)