I suggest they would be combined.
To me, a "kingdom" refers to some sort of region that is ruled by monarchs, but the kingdom may be ruled by multiple different monarchies through the ages. Additionally, questions about "monarchy" can cover things such as changes to the monarch's power, the life of the monarch, etc. Those questions could also be framed from the viewpoint of the kingdom, but they would not necessarily be questions about the kingdom itself. I just don't think that kingdom --> monarchy == monarchy --> kingdom. It's not 1-1.