The Kingdom of Redonda is a micronation based on the tiny island of Redonda, situated between the islands of Nevis and Montserrat in the Caribbean Sea.

The island, which is uninhabited, is currently a dependency of the country of Antigua and Barbuda.

Redonda also is, or appears to be, a micronation which may, arguably and briefly, actually have existed as an independent kingdom during the 19th century. The title to this supposed kingdom is still contested to this day. The Kingdom of Redonda is also often associated with a number of supposed aristocratic members, whose titles are given out freely by whoever is currently the king. As of today, there are a number of different individuals in several countries who claim to be the sole legitimate king of Redonda.

The idea of the kingdom appears to originate with Matthew Phipps Shiell (1865-1947) an author of fantasy fiction. He claimed that in 1865, his father Matthew Dowdy Shiell, from the nearby island of Montserrat, proclaimed himself to be the rightful, and supposedly legal, king of the island of Redonda in order that he might establish his son as the rightful heir to the throne. This story, as first recounted by the son in a promotional leaflet for his books, may be partly or entirely fictional.

Following Matthew Phipps Shiell death in 1947, John Gawsworth took over as King of Redonda as King Juan I, and Arthur John Roberts was crowned as King Juan II after Gawsworth death in 1967. When Roberts died in 1989, a number of individuals claimed their right to the throne, among them, William Leonard Gates from Great Britain, Robert Williamson from the United States, or the famous writer Javier Marías from Spain.