Monarchism is the advocacy of the establishment, preservation, or restoration of a monarchy as a form of government in a nation. A monarchist is an individual who supports this form of government out of principle, independent from the person, the Monarch.
In this system, the Monarch may be the person who sits on the throne, a pretender, or someone who would otherwise inhabit the throne but has been deposed. Any person who claims the throne from which an ancestor has been deposed is known as a pretender.
Monarchism focuses on the system of monarchy, and some people argue that the term "monarchist" must be distinguished from the term "royalist".
A royalist supports a particular monarch as head of state for a particular kingdom, or of a particular dynastic claim. In the abstract, this position is royalism. It is distinct from monarchism, which advocates a monarchical system of government, but not necessarily a particular monarch. Most often, the term royalist is applied to a supporter of a current regime or one that has been recently overthrown to form a republic.
In the United Kingdom today, the term is almost indistinguishable from "monarchist," because there are no significant rival claimants to the throne. Conversely, in 19th-century France, a royalist might be either a Legitimist, Bonapartist, or an Orléanist, all being monarchists.