It's not actually up to the Census. They're following OMB Directive 15 on race reporting standards for all federal data collection. You can read it here: https:

It's not actually up to the Census. They're following OMB Directive 15 on race reporting standards for all federal data collection. You can read it here: https://www.govinfo.gov/content/pkg/FR-1997-10-30/pdf/97-28653.pdf https://www.govinfo.gov/content/pkg/FR-1997-10-30/pdf/97-286... This is the latest version, but it was originally published in 1977 and based on the idea that humanity consisted of only four races. The reason it asks what "kind of white person" you are is the 1997 update was in response to criticism that this wasn't fine-grained enough, so they split Pacific Islander into its own group and split white people into Hispanic and Non-Hispanic. The idea of there only being four races in the world comes from Carleton Coon's publications from the early 60s. He had a theory that human races all evolved independently from Homo erectus to Homo sapiens, in contrast to the more widely accepted "out of Africa" theory, and that this accounts for why some races, according to him, are "more civilized" than others. That is, humans left Africa in a savage state and evolved into sapiens form and developed civilization much earlier in Europe and Asia, again, according to him. I think it should be obvious why making a theory like this the basis of US official federal standards for race is somewhat controversial, but as we know, laws and regulations change slowly, if ever, so the Census is kind of stuck defending work they're legally charged with doing, and this data is used to assess things like racial equity of federal spending and assessment of the fair housing act and what not. It's kind of a relic of our shitty history, but it's there.