Stephen Van Rensselaer III was an American landowner, businessman, militia officer, and politician. A graduate of Harvard College, at age 21, Van Rensselaer took control of Rensselaerswyck, his family's manor. He developed the land by encouraging tenants to settle it and granting them perpetual leases at moderate rates, which enabled the tenants to use more of their capital to make their farms and businesses productive.

Rensselaerswyck was a Dutch colonial patroonship and later an English manor owned by the van Rensselaer family located in the present-day Capital District of New York in the United States.