Edisto Island is one of South Carolina's Sea Islands, the larger part of which lies in Charleston County, with its southern tip in Colleton County. The town of Edisto Beach is in Colleton County, while the Charleston County part of the island is unincorporated.The island, town, and Edisto River are named after the historic Edistow people, a Native American sub-tribe of the Cusabo Indians, who inhabited the island as well as nearby mainland areas.