Was there really a sudden Native American population boom?

Forget about Martin Scorsese’s “Killers of the Flower Moon”: We’re pretty sure the most anticipated debut related to Native Americans this year is a much-delayed and much-less-snappily named release from the U.S. Census Bureau known as Detailed Demographic and Housing Characteristics File A.

The report provides the most detailed data we’ve ever had on America’s racial and ethnic origins, including stunningly exhaustive data on nearly 1,200 tribes, native villages and other entities. We hoped it would shed light on one of the biggest mysteries in the 2020 Census: Why did the Native American...