This article offers a historiographical interpretation of an exceptionally rich personal archive; namely, fond Number 6: “Tŭrgovska kŭshta [Commercial Company] ‘Khristo P. Tŭpchileshtov’”, kept in Bŭlgarski istoricheski arkhiv (Bulgarian Historical Archive), Narodna Biblioteka (National Library) “Sv. Sv. Kiril i Metodiĭ” in Sofia. The analysis is organized around three issues: the biography of the archive’s founder; the acquisition of the archive by the National Library; and the ways the archival material has been interpreted in the Bulgarian historiography. More specifically, I am discussing the ideological motivation behind the arrangement of the documents and their multiple uses in the historical studies during the interwar, socialist, and post-socialist periods. There is a paradoxical situation: the fond Number 6 is not only one of the biggest archival personal collections but also one of the least actually used archives. And yet, one of the most cited in Bulgarian historical research. Accordingly, the fond provides a window into more substantial historiographical issues. I am arguing that the way the fond was catalogued by its first archivist, predetermined the way it was interpreted in the subsequent historiography; namely, within the confines of a national narrative almost ignoring the ample information about the Ottoman, Balkan, and European context.