The Calusa (kəˈluːsə ) were a Native American people of Florida's southwest coast. Calusa society developed from that of archaic peoples of the Everglades region. Previous indigenous cultures had lived in the area for thousands of years.
At the time of European contact in the 16th and 17th centuries, the historic Calusa were the people of the Caloosahatchee culture. They developed a complex culture based on estuarine fisheries rather than agriculture. Calusa territory reached from Charlotte Harbor to Cape Sable, all of present-day Charlotte, Lee, and Collier counties, and may have included the Florida Keys at times. They had the highest population density of South Florida; estimates of total population at the time of European contact range from 10,000 to several times that, but these are speculative.
Calusa political influence and control also extended over other tribes in southern Florida, including the Mayaimi around Lake Okeechobee, and the Tequesta and Jaega on the southeast coast of the peninsula. Calusa influence may have also extended to the Ais tribe on the central east coast of Florida.
Early Spanish and French sources referred to the tribe, its chief town, and its chief as Calos, Calus, Caalus, and Carlos. Hernando de Escalante Fontaneda, a Spaniard held captive by the Calusa in the 16th century, recorded that Calusa meant "fierce people" in their language. By the early 19th century, Anglo-Americans in the area used the term Calusa for the people. It is based on the Creek and Mikasuki (languages of the present-day Seminole and Miccosukee nations) ethnonym for the people who had lived around the Caloosahatchee River (also from the Creek language).
Juan Rogel, a Jesuit missionary to the Calusa in the late 1560s, noted the chief's name as Carlos, but wrote that the name of the kingdom was Escampaba, with an alternate spelling of Escampaha. Rogel also stated that the chief's name was Caalus, and that the Spanish had changed it to Carlos. Marquardt quotes a statement from the 1570s that "the Bay of Carlos ..