Was reading about Iron Mountain and saw that the original purpose behind the company was "protecting corporate information from nuclear attack and other disasters." This was in 1951, right after the world wars.
Was losing a lot of information just a projected worry, or was this something that really happened? Would a Dresden resident who survived the firebombing find that their birth certificate was gone and there was no evidence they existed as a German citizen? Did Mitsubishi lose engineering schematics? Would there have been people who owed money to German banks that found that there was no record of their debt?
One of the more baleful instances of collateral damage from both the bombing campaign and the conduct of the war in general was the destruction of various historical archives. UNESCO has a pdf of especially notable losses from libraries, research institutions, and other archives. Although many states sought to preserve this data, such efforts were often a relatively low priority in wartime and incomplete. For researchers of German history, finding out that an document or source listed in a database was destroyed by the war is an unfortunate but not uncommon experience.
Some of this archival destruction was also quite wanton and deliberate. When the Germans occupied Vilna, one of the centers of Jewish publishing in Eastern Europe, German archivists preserved only a fraction of the materials there for a proposed postwar museum of Judiaca ( a previous answer goes in depth on this museum) and pulped the rest. Defeated militaries were also quite active in attempting to destroy data about military technology just prior to the surrender. The Japanese destroyed a large number of records on the design and construction of their Yamato-class superbattleships, which is part of the reason why the photographic record of these ships is so thin.
The loss of so many record complicated the postwar resettlement of so many displaced person (DPs), especially since German racialist domination of Europe meant that forgeries and faked identification papers was a growth industry in wartime.