Lumberton is a city in Robeson County, North Carolina, United States. As of 2020, its population was 19,025. It is the seat of Robeson County'…Lumberton is a city in Robeson County, North Carolina, United States. As of 2020, its population was 19,025. It is the seat of Robeson County's government. Located in southern North Carolina's Inner Banks region, Lumberton is located on the Lumber River. It was founded in 1787 by John Willis, an officer in the American Revolution. This was developed as a shipping point for lumber used by the Navy, and logs were guided downriver to Georgetown, South Carolina. Most of the town's growth took place after World War II.