The census is older than the Chinese, Egyptian, Greek and Roman civilizations, dating back to the Babylonians in 4000 BCE who used a census as an essential guide to how much food they needed to find for each member of the population. Evidence suggests that they noted census records on clay tiles – an example is held by the British Museum.
From around 2,500 BCE the Egyptians used censuses to work out the scale of the labor force they would need to build their pyramids. They also used the information to plan how they would share out the land after the annual flooding of the Nile.
China too, began to take censuses around this time. The most well known, taken by the Han Dynasty in 2 CE, and considered by experts to be relatively accurate, recorded 57.67 million people living in 12.36 million households.
The Romans conducted censuses every five years, calling upon every man and his family to return to his place of birth to be counted in order to keep track of the population. Historians believe that it was started by the Roman king Servius Tullius in the 6th century BCE, when the number of arms-bearing citizens was counted at 80,000. The census played a crucial role in the administration of the peoples of an expanding Roman Empire, and was used to determine taxes. It provided a register of citizens and their property from which their duties and privileges could be listed.