United States Census Historical Background
The first census law in the United States was signed by President Washington in March of 1790. He assigned the task of taking the census to the seventeen United States Marshalls. The census was taken using existing civil divisions. The early census records were an enumeration of persons. As time progressed, different information was included on the census forms.
Szucs, Loretto Dennis and Sandra Hargreaves Luebking, ed. The Source, A Guidebook to American Genealogy. (Provo, Utah: Ancestry, 2006).