South Salem is a hamlet within the town of Lewisboro. After purchasing land from the local natives, the first settlers established themselves around South Salem. The town was formed as "Salem" in 1747. By 1790 the town assumed its current dimensions as lands were removed for other towns. The name changed to South Salem in 1806. John Lewis, a financier, requested that the town be given his name and established a fund for the town, though he did not follow through on his promise of a railroad link.
Within the town of Lewisboro, there are 7 lakes. Lake Waccabuc, Lake Oscaleta, and Lake Rippowam are interconnected and are collectively known as the Three Lakes, and are natural (not man-made) lakes. Lake Waccabuc is the largest and most well known of these, and the area of town named after it has a separate post office. Lake Oscaleta and Lake Rippowam are also called the Twin Lakes, probably because of Twin Lakes Village, a development which runs between them. The other lakes in town are Lake Truesdale, Lake Katonah, Lake Kitchawan, and Timber Lake. Recognizing the importance of the lake communities in the town, in 2007 a Lakes Committee was formed by the Town of Lewisboro. The Hamlet of South Salem has in its center a Post Office, Town Hall, Library and recycling center.
The Katonah-Lewisboro School District serves the town of Lewisboro, the northern third of Bedford, including the hamlet of Katonah and portions of the towns of Pound Ridge and North Salem. It has four elementary schools, one middle school and one high school. These are: Katonah Elementary School, Increase Miller Elementary School, Lewisboro Elementary School, Meadow Pond Elementary School, John Jay Middle School and John Jay High School.