Throughout the history of man, enumerations have been taken of the residents of nations. An "enumeration" is a counting or numbering of something. Therefore, in the case of a nation's enumeration, it entails a counting of the nation's residents. Another word for the counting, or enumeration, of a nation's residents is "census".
History has been witness to some very famous enumerations. According to the Bible (ref: Numbers, Chapter 3), God spoke to Moses in the wilderness of Sinai, and told him to: "Number the children of Levi after the house of their fathers, by their families; every male from a month old and upward shalt thou number them." The Bible (ref: St. Luke, Chapter 2) also records the census decreed by Caesar Augustus just prior to the birth of Jesus the Christ in order to obtain a count of the people from whom he would collect a tax.
In the year 1086 another famous census was undertaken by William the Conqueror of England. Known as the Domesday Book, this census was a survey of all the residents of England and their holdings at the time. It was one of the first census in which livestock were accounted for. It provided a wealth of information about the population and their property.
The first federal census to be taken in the United States was authorized by the Congress for the year 1790. A new census would be taken every ten years. It was decided that, in order to avoid publishing information regarding living individuals to the public, that the results of each census would be made available to the public only after seventy (70) years had passed. In 1952 it was decided that the period of time between release of any new census would be seventy-two (72) years. Then, an act of the Congress is required to release the information. After its release, the pages of census records are microfilmed and the original paper copy is destroyed. The Census Bureau does not maintain copies of the Census; instead regional centers make copies of the microfilm available to researchers and family genealogists.