This is a list of the oldest people by country and in selected territories. It includes the individual(s) for each given country or territory who are reported to have had the longest lifespan. Such records can only be determined to the extent that the given country's records are reliable. Comprehensive birth registration is largely a 20th-century phenomenon, so records establishing human longevity are necessarily fragmentary. The earliest comprehensive recordkeeping systems arose in Western Europe. For example, the United Kingdom organized a central recordkeeping system for England and Wales in 1837, making it compulsory by 1874.