The fate of Hebrew book collections was determined by many of the same factors that tempered Jewish history. The intense intellectual activity and a high rate of literacy that so frequently characterized Jewish society encouraged the production and cumulation of large numbers of manuscripts (and later, printed books) but also led to their steady deterioration through constant use. Persecutions, pogroms, exiles and mass book burnings over the centuries further depleted the number of Hebrew books so that today there are probably manuscripts extant, fewer than 100,000 half of them dating to the Middle Ages. These manuscripts are scattered in over 700 collections housed in public and university libraries, synagogues, monasteries and private homes in over twenty five countries on all six continents.
Manuscripts are in a sense the "raw material" for research in Hebrew literature. Without manuscripts at his disposal the scholar cannot establish accurate texts. If his library includes only printed books his studies in certain fields such as kabbalah, philosophy or poetry will be severely limited as the number of unpublished works in these fields rivals or exceeds the number of printed works. In order to preserve, fully appreciate and study all the treasures of Jewish written culture it is necessary to concentrate all the Hebrew manuscripts in one center and to provide a comprehensive union catalogue of all the works copied in them. David Ben Gurion understood this!
In March 1950, Ben Gurion, then prime minister of Israel, was enjoying a hard earned vacation in Tiberias. The problems facing the prime minister of a state still less than two years old were enormous: security, economy, immigration and settling the land, to name a few. Nevertheless, Ben Gurion found the time to write a long letter to his minister of finance requesting a large sum for the establishment of an Institute of Manuscripts in Jerusalem for the purpose of microfilming all the Hebrew manuscripts in the world. The letter was sent to the minister and copies to all the other members of the government on March 5, 1950. A few days later the government voted to establish the Institute of Hebrew Manuscripts under the auspices of the Ministry of Education and Culture.
Dr. Nehemiah Allony, the first director of the Institute, set out with unbounded energy to accomplish the task envisioned by Ben-Gurion. During the first decade of the Institute's existence Allony made eight trips to Europe persuading and convincing the directors of most of the major libraries of the continent to have their Hebrew manuscripts copied on microfilm. By the time he completed the period of his directorship in 1963 - when the Institute was transferred to the Jewish National and University Library (JNUL) on the Givat Ram campus of the Hebrew University and acquired its new name, the Institute of Microfilmed Hebrew Manuscripts (IMHM) - the collection of microfilms had grown to over 15,000. Now, over fifty years later, the number of microfilms on file at the IMHM exceeds 76,000; other formats of reproduction include slides, Photostats, microfiche and digital scans, and total in the thousands. Almost all the major collections in the world have been, or are in the process of being filmed/digitized. Until the dissolution of the USSR access to manuscripts in Russia was very limited, but during the 1990s the major collections in Moscow and St. Petersburg, numbering over 20,000 manuscript items (complete and partial codices) were filmed and cataloged. In the past decades, genizot of manuscripts kept as binding material for printed books have been discovered and filmed/digitized throughout Europe.