If we think about the pieces of the past that are “lost to history,” we likely think of events and places and people from decades ago. If you follow this blog, you’ll know of my enthusiasm for genealogy, so the past lives of many people in my family become vague and irretrievable only when I hit the 1500 and 1600’s (like my ancestor’s 1657 death, which was considered so suspicious the sheriff convened an inquest).

That in mind, it may come as a surprise that barely fifty years ago—in 1973, when the Beatles were still a group—a massive fire near St. Louis, Missouri, destroyed millions of records of U.S. Army personnel from both world wars and other 20th century conflicts. At the time, the federal government preserved a single copy of the Official Military Personnel File (OPMF) of every person who served. You may know how difficult it can be to pry information out of veterans—very often they simply “don’t want to talk about it.” When their descendants get bitten by the family history bug, these records are a way in.

At least they were. But, after the fire, 80 percent of them—17,517,490—personnel records were gone. In her article for Wired magazine, “Soldiers Stories Lost,” author Megan Greenwell quotes archivist Terry Cook: “Archives are constructed memories about the past, about history, heritage, and culture, about personal roots and familial connections, and about who we are as human beings.” The fire left a big hole in that memory.

What followed has been a massive and ongoing effort by the National Archives to save everything it can. It first had to dry the records, soaked by the days-long efforts of 42 local fire departments to quench the fire. It has had to fight mold. Some documents merely singed, some were utterly lost, and some would have to be kept in special storage forever. When staff members receive a request for information, if it is for one of the 17.5 million burned records, they first determine whether any record at all remains, any bit of the original. If anything can be retrieved, they’ve become expert in handling it, scanning it, and sending it to the requester. If all else fails, an infrared camera may detect ink patterns on a sheet that looks thoroughly blackened.

Although it may seem that the Archives efforts have been painfully slow, ironically, time has been on its side. Technological advances, like that infrared camera, didn’t exist until recently. Had they hurried the job, the opportunity to use it would have been foregone.

With the precise vision offered by hindsight, the building could have been better protected, a few trash can fires could have been investigated more thoroughly, electrical problems could have been corrected, the design could have included a sprinkler system and firewalls. Eventually, a careless smoker confessed the fire may have been his fault, but the extent of damage was such that the authorities concluded it’s impossible to pinpoint a cause.

What a relief it must have been when, in 2011, the staff and records moved into a new, much more fireproof facility, a tribute to their dedication in continuing this laborious work into a sixth decade!