Museum founder Vinzenz Maria Süss (1802–1868) already started to collect Salisburgensia, books, cards, graphics and works on paper on Salzburg art and history. 1870 marked the publication of the first printed catalogue of the Salisburgensia kept in the library of the Municipal Museum Carolino Augusteum; this included printed works, manuscripts, sheet music etc., also maps, plans and views, on a total of 117 pages. Since then, the holdings were increased through bequests and purchases, but depleted again through the effects of war and de-acquisitioning (sale, transfer to other museums and archives). Since the nineteenth century, the museum has collected new items including ex libris, obituary pictures, coats of arms and legacies of well known Salzburg artists and writers; parts of these can now be found in the Photographic and Graphics Collection.

The collection’s range encompasses original autographs of the famous Christmas carol “Silent Night” by Joseph Mohr and Franz Xaver Gruber from the pre-1848 Revolution period (“Vormärz”), as well as poster stamp albums from 1914 to 1920, and the Missa Salisburgensis by Heinrich Ignaz Franz Biber, also the cookery book by Maria Euphrosine Khumberger of 1735 containing 285 recipes.

The collection contains around 5,000 manuscripts and autographs. Furthermore, it holds realia and personal collections, family registers, diaries and obituary card collections. Then there are theatre bills and programmes of the Salzburg Landestheater and the Salzburg Festival. The music manuscripts and prints amount to 2,700 items. The very extensive poster collection was entered into a computer database and already includes 11,000 catalogued items. Obituary pictures and the coat of arms collection are also included in the inventory. An important section also arose through reception of the legacies of well known Salzburg personalities, including Richard Mayr, Anton Faistauer, Georg Trakl (Geipel Collection), Joseph Messner and August Brunetti-Pisano.

The Salzburg Museum Association supports the museum in its acquisitions. In December 2014, the museum succeeded in purchasing a journal by the museum patroness Caroline Augusta. Most of the new acquisitions for the collection stem, however, from gifts made by members of the Museum Association and the Salzburg populace.

Only a small part of the special collections is presented in the diverse exhibitions in the Neue Residenz. The library has the most important function: in the reference library, researchers and all interested users have access to all holdings for studying and working on them. Planning for the coming years includes linking the museum library to the Internet; this aims not only to enhance the library’s media presence, but also to improve research options for the visitors.