The collection, which originated in August - September 1968, contains key documents from the first seven days of the occupation of Czechoslovakia by the Warsaw Pact troops. Based on these documents, a five-page book with almost a hundred illustrations was created. This book was created by historians from the Czechoslovak Academy of Sciences, Milan Otáhal and Vilém Prečan, and all materials were collected during the first seven days of the occupation of Czechoslovakia. The book, which was published in October 1968 under the title Seven Prague Days 21-27 August 1968, was marked as study material for internal use and was not available in any bookstores. Nevertheless, the news of its existence soon spread across the country, and by mid-December 1968, information on the publication of Seven Prague Days was sent to the world press, with the exception of the Soviet Union and its then-satellites. The demand for this unique documentation and the response to it was stunning. For its tragic content, and simple black cover, the nickname "Black Book" quickly emerged. The materials in the book were collected on the streets of Prague and from both public and private locations. The book was written by historians in an attempt to preserve as much as possible of the evidence and testimony of those seven days in September 1968.
The authors of the book encountered many problems while compiling it. Above all, they had to clearly state the timescale of the book, deciding to include data on some of the most important events that took place between 11:00pm on August 20, and August 27, with the inclusion of speeches and documents from state bodies and officials which were given or published before August 28 or 29, but were closely related to these events. Then, for practical reasons, they had to restrict themselves only to events that took place in Prague. They took full account of the fact that Prague is the seat of central state, party and social bodies and institutions.
The fate of this book was extraordinary. It is the only book in modern Czechoslovak history that has led to diplomatic interstate correspondence, it was dealt with by the Presidency of the Czechoslovak Government and the supreme ruling Communist Party of Czechoslovakia. A few months after its distribution, uniformed police officers visited the 800 Czechoslovak institutions to whom the book was sent, ordered to halt publication of it and fulfil the Soviet demand that the book be destroyed. That is why only a small number of copies were preserved. In the following years, the book spread abroad in a number of foreign-language translations, and finally in 1990 there was again a mass printing in Czechoslovakia.
Although it was a legal publication of the Institute of Sciences of the Czechoslovak Academy of Sciences, it was the subject of an extensive investigation by the General Prosecutor's Office of the Czechoslovak Socialist Republic and the State Security Investigation Administration. The ban on publication was formally lifted only in 1980. At the time of the investigation, 30 witnesses were heard, and expert opinions were given. Even though only the authors of the book were ultimately convicted for the publication and distribution of the "Black Book", its editors Milan Otáhal and Vilém Prečan were released from the Czechoslovak Academy of Sciences in 1970, prosecuted, and could only work in manual labour. Prečan and Otáhal wrote in the preface of the “Black Book” that “This bitter experience of the generations of historians (who have struggled with the lack of sources for historical events) has led us to this experiment and we have also taken over the duties the Historical Institute has as a research center, and last but not least, we wanted to give an incentive - perhaps even a foundation - to create similar documentation elsewhere, in regions, districts or factories.”
The story of this book is probably unique in the history of modern world literature and in the history of Czechoslovakia, it is part of the dramatic series of events that shook Czechoslovakia in 1968 and for some time thereafter.
This collection, which gathers official documents, newspaper articles, statements and documents of the public's spontaneous reaction to occupation, was hidden in the seventies by Vilém Prečan. After his departure to exile in 1976, he managed to get to the West via a smuggling channel, where the book was included in the Czechoslovak Documentation Center of Independent Literature, founded in 1986. In September 2000 the Documentation Center and its collections were moved to the Czech Republic. In 2003, CSDS made an agreement with the National Museum in Prague; the CSDS collections, including the "Black Book", were donated to the National Museum.