Petersburg was formed from parts of Dinwiddie, Prince George, and Chesterfield Counties. It was established in 1748 and incorporated as a town in 1784. In the latter years the towns of Blandford, Pocahontas, and Ravenscroft were added to Petersburg. It was incorporated as a city in 1850.

The Sanborn Map Company was founded by D. A. Sanborn, a surveyor from Massachusetts, in 1866. The maps allowed fire insurance underwriters and policy holders to more accurately protect the risks of business even if a building was not able to be inspected in person and to prevent an insurance premium from being set too low or high. Aside from fire insurance companies, the Sanborn Maps are useful to people involved in government, business, engineering, health and sanitation, planning and zoning, public works, tax assessment, education, highway development, public libraries, architects, geographers, environmentalists, water works, banking, mortgages, and life insurance, utilities and many other professional industries. Sanborn Maps also serve as historical documents for cities and towns and are important to those involved in social history, local history, architectural history, genealogy, urban studies, and preservation. The detail provided by the Sanborn Maps about each city in terms of its physical make-up, as well as the infrastructure of each city or town, provides important insights into a locality for professionals of all sorts.