Genealogy nerds like me frequently weep and fan themselves to exhaustion over a gaping hole in America’s historical record: The 1890 U.S. Census is gone.

The original was destroyed. No copies exist. No scans. No photos. Therefore nearly all of it has been erased from history.

That, my friends, is no small deal. Every ten years since 1790, we have records of who lived where, with what family members, how old they were…and assorted other nuggets of personal history. Try to research your family history, and you will quickly understand what a treasure chest each census is–“oh look, my great-great grandfather was a ‘gentleman’ by profession in 1910, while in 1900, he was a fruit peddler.” I can tell you when my great grandparents took in my young, distant cousins (after their mother’s dress caught on fire from the stove, and her instincts to run across a field to a neighboring home while aflame were fatal). I can point to the empty, weed-filled lot in Detroit and say with confidence, “Yep, that was my family’s home for over fifty years.” I know all of this because of census records.

But thanks to a deep and bizarre mystery that culminated in the obliteration of the 1890 U.S. Census, I cannot track much of my American ancestors’ history and movement from 1881 to 1899. What happened to it? According to most stories it burned up in 1921. But that isn’t really the truth. Something far stranger happened, and to this day it isn’t clear at all why it happened.

This is the story of the 1890 U.S. Census and how it went from controversial marvel, to disappearing pile of ash. What you are about to read is a tale of greed, incompetence, and mystery.