The oldest and preserved inventory book (Catalogo Reinventionali) of the Hungarian Natural History Museum, dates back to 1821. The second data entry of this book (following a mumia aegyptiaca) was about a bat conserved in spirit and the development of the mammal collection has been unbroken since then. The havoc of the World Wars and the Revolution of 1956 caused serious damage to the Museum, but apart from some large mounted mammals this collection survived those years intactly. Although the mammal collection does not belong to the largest ones considering the number of the materials, all the curators (according to their main interest) significantly developed that. In addition to the exploration of the Carphatian Basin in the early 19th century exotic animals began to enrich the collection either via purchase or collecting works of amateurs and professionals, such as János Xántus, Lajos Bíró or Kálmán Kittenberger. Several large private hunting trophy collections were also donated.