Yemassee is a town in Beaufort and Hampton counties in the U.S. state of South Carolina. The population was 807 at the 2000 census. Yemassee is also very near the borders of Colleton and Jasper counties and is often considered to be the geographical center or heart of the Lowcountry region. The town is divided by the county line between Beaufort and Hampton Counties, which follows the roadbed of the CSX railroad. Most of the town's population presently lies within Hampton County (as of 2006). As defined by the U.S. Census Bureau, the Beaufort County portion of Yemassee is included within the Hilton Head Island–Beaufort Micropolitan Statistical Area. Yemassee hosts one of the few commercial breeding facilities of non-human primates in the entire United States (Alpha Genesis, Inc.). Also, the Frank Lloyd Wright designed Auldbrass Plantation house and outbuildings lie just outside the town limits of Yemassee.
The town takes its name from the Native American tribe of the same name, the Yamasee, which was the most important Indian ally of South Carolina until the Yamasee War of 1715. The first attack that began the Yamasee War occurred in the Yamasee town of Pocotaligo, today part of the town of Yemassee.
The site of the present town is surrounded by both Revolutionary and Civil War sites. The remains of Civil War field fortifications can be observed along U.S. 21 & 17A between Yemassee and Pocotaligo (that section of highway is now a part of Yemassee, as the town has now greatly expanded into Beaufort County [as of 2006]). As of 2006 there is a building boom underway in and around Yemassee. The rural aspect of Yemassee is now (as of 2006) beginning to disappear with the construction of large numbers of new homes and very large housing developments in the area.