Ancient ceremonial and burial mounds on Caladesi Island show pre-European activity by countless generations of Native Americans. After the Spanish conquest of La Florida in the 1500s, the island served as a site for seasonal encampments and fish ranches for 300 years. Tall ships moored offshore, and soldiers and sailors came ashore to hunt, fish, and camp, while smoked and salt fish, plumes, and hides were traded with Cuba. The British ruled Florida for two decades, including the years of the American Revolution, before the Spanish regained control in 1783. Florida became a U.S. territory in 1821 and a state in 1845. In the 1880s, Swiss immigrant Henry Scharrer, a self-taught naturalist and protector of Caladesi, established a 156 acre homestead there. His daughter Myrtle, born there in 1895, became known for rowing daily to Dunedin to attend school and for writing a memoir of Florida pioneer life, Yesteryear I Lived in Paradise. Visitors to the homestead included Fritz Kreisler, Robert Lincoln, Eddie Rickenbacker, and Carl Sandburg. Caladesi Island became a Florida State Park in 1967 and remains a rare surviving example of a naturally evolving barrier island with coastal dune, mangrove, maritime hammock, and pine flatwood habitat.