The arctic circle 66.56083N of the equator. It is one of the two polar circles and the most northerly of the five major circles of latitude. Eight countries can be found withing the arctic circle; Norway, Russia, Finland, United States(Alaska), Canada (Yukon, Northwest Territories, and Nunavut), Denmark (Greenland), and Iceland (where it passes through the small offshore island of Grímsey).
It can either be absolute monarchies or constitutional monarchies, whatever one fits more with your questions or just simply, monarchy. Hope this helps!