Celtania had an archives system for ages, as the Great Library of Trondheim was duplicated as soon as possible. Nowadays, it keeps every kind of documents in digitized and dematerialized versions (since the originals were often damaged by fights and radiation).
Celtic archives reached its current form when Celtania switched from Democracy to Communism : compromising documents were progressively hid. Theoretically, only citizens and soldiers have a (limited) access to national records, the completeness of it increasing as the rank does. Only a few state advisors and ministers have a complete access to the data, as they can themselves modify or hide documents without having to mention it.