Monticore is a kingdom and the homeland of Prince Throckmorton.
Background[]
Little else is known about the kingdom. It can be assumed that it probably lies fairly close to Daventry, as Prince Throckmorton traveled from there to attempt to court Rosella.
It maybe one of the western and southern kingdoms which the people of Daventry fled to to escape the destruction of the Three-headed dragon. These are the many kingdoms the continent is divided into, most of them small and only a day or three's journey by foot in extent. These fiefdoms sometimes war or battle with each other for reasons their rulers care about, and shrink or grow depending on their martial fortunes. They seemingly come and go with the seasons, and few are remembered after their passing.
Behind the scenes[]
Due to naming conventions this could also be a house (or manor) name or simply a surname (however it doesn't seem to relate to any common European surname). It appears likely a variation on "manticore", a mythological beast.