Magnolia is a city in Pike County, Mississippi and the county seat. The population was 2,420 at the 2010 census. Magnolia is within the McC…Magnolia is a city in Pike County, Mississippi and the county seat. The population was 2,420 at the 2010 census. Magnolia is within the McComb, Mississippi Micropolitan Statistical Area. Magnolia was founded in 1856 by Ansel H. Prewett, a local civic leader and cotton planter. Knowing that the approaching New Orleans, Jackson, and Great Northern Railroad would need a station for water and fuel, Prewett sold a right-of-way to the railroad company – for one dollar, according to legend – and divided a section of his plantation into town lots, which he sold to investors. Prewett, while serving as temporary sheriff of Pike County, was killed by outlaws in the early 1870s escorting a prisoner on the very railroad that made Magnolia a viable community.