This Encyclopedia is the first to compile pseudonyms from all over the world, from all ages and occupations in a single work: some 635,000 pseudonyms of roughly 270,000 people are deciphered here. Besides pseudonyms in the narrower sense, initials, nick names, order names, birth and married names etc. are included. The volumes 1 to 9 list persons by their real names in alphabetical order. To make the unequivocal identification of a person easier, year and place of birth and death are provided where available, as are profession, nationality, the pseudonym under which the person was known, and finally, the sources used. The names of professions given in the source material have been translated into English especially for this encyclopaedia. In the second part, covering the volumes 10 to 16, the pseudonyms are listed alphabetically and the real names provided.