Wenham is a town in Essex County, Massachusetts, United States. The population was 4,979 at the time of the 2020 census. The town of Wenham, originally settled in 1635 and incorporated in 1643, has retained much of its historic character and rural scenery. It is a town of many open views of farm lands, lakes, woodlands, historic homes and old stone …Wenham is a town in Essex County, Massachusetts, United States. The population was 4,979 at the time of the 2020 census. The town of Wenham, originally settled in 1635 and incorporated in 1643, has retained much of its historic character and rural scenery. It is a town of many open views of farm lands, lakes, woodlands, historic homes and old stone walls that accompany its winding tree-lined roads. It features nearly 300 acres of parks, playgrounds and recreational lands.