There are 4 US Post Offices in Greene County serving a total of 11,921 residents equating to 2,980 residents per post office. It's estimated that approximately 19,027 packages are handled across the 4 county post offices annually. Greene County is a county located in the U.S. state of Mississippi. As of the 2010 census, the population was 14,400. Its county seat is Leakesville. The county was established in 1811 and is named for General Nathanael Greene."