Estero was established and incorporated by the followers of Cyrus Teed, who proposed a theory that we live on the inside of the Earth’s outer skin, and that celestial bodies are all contained inside the hollow Earth. This theory, which he called Koreshan Unity, drew followers to purchase and occupy a 320-acre (1.3 km2) tract in 1894. They were business-oriented and lived communally, prospering enough to found their own political party (“The Progressive Liberty Party”) and incorporate the town on September 1, 1904 as Estero.
The 1908 death of Dr. Teed (who claimed to be immortal) was a critical blow to the group’s faith, whose membership dwindled into the 1960s. The Foundation remains as “The College of Life Foundation,” which contributed (for example) at least $25,000 to the Gulf Shore Playhouse in or around 2007. The Koreshans’ original tract is now owned by Florida as the Koreshan State Historic Site. Estero is now an incorporated area of Lee County, as of December 2014, and is known as the Village of Estero.