The Kingdom of the Netherlands, commonly known simply as the Netherlands, is a sovereign state consisting of a collection of constituent territories united under the monarch of the Netherlands, who functions as head of state. The realm is not a federation; it is a unitary monarchy with its largest subdivision, the eponymous Netherlands, predominantly located in Northwestern Europe and with three smaller island territories located in the Caribbean.
The four subdivisions of the Kingdom—Aruba, Curaçao, the Netherlands, and Sint Maarten—are constituent countries (landen in Dutch; sing. land) and participate on a basis of equality as partners in the Kingdom. All four are autonomous with their own parliaments, however, the Kingdom itself is administered in the constituent country of the Netherlands, which comprises roughly 98% of the Kingdom's land area and population, with matters like foreign policy and defence done on behalf of the entire Kingdom.
The vast majority of land area of the constituent country of the Netherlands is in Europe, while its three special municipalities (Bonaire, Saba, and Sint Eustatius) are located in the Caribbean, as are the other three constituent countries.