Property rights and control of commerce were contentious concerns between nations, charter companies, and individuals during the eighteenth century, the setting of Mason & Dixon. England and France are engaged in a power struggle for colonies in North America and in India. The British East India Company has a monopoly to control trade routes and commodities at Tenerife, St. Helena, and Capetown, South Africa. In America, heirs of William Penn and Lord Baltimore argue over property boundaries between Pennsylvania and Maryland, and in 1763, Charles Mason, an astronomer, and Jeremiah Dixon, a surveyor, arrive in Philadelphia to settle this eighty-year-old dispute. The struggle for power and control over land and commerce provides the motivation and framework for this encompassing, complicated vision of social values and practices that became the founding principles of America.

Neither Mason nor Dixon has aristocratic ties. Mason is the son of a miller.

His...