Canopus IV is a planet, the fourth planet in the Canopus star system. Canopus IV is well known for its excellent antiques shops.

Captain James T. Kirk visited the shops on Canopus IV several times in the 2260s, to search for hard copy books. On one occasion, Kirk acquired a copy of Jules Verne's, "Twenty Thousand Leagues Under the Sea". (TOS novel: Yesterday's Son)

During the mid-23rd century, the Romulan Centurion Vonath and his lover, the Orion Marta launched an attempted conquest of the world. Marta was captured by Starfleet in 2266 (Decipher RPG module: Narrator's Guide).

It is not stated if this conquest was successful or not.