An incunabulum is a book, single sheet, or image that was printed — not handwritten — before the year 1501 in Europe. The origin of the word is the Latin incunabula for "swaddling clothes", used by extension for the infancy or early stages of something. The first recorded use of incunabula as a printing term is in a pamphlet by Bernhard von Mallinckrodt, De ortu et progressu artis typographicae ("Of the rise and progress of the typographic art"), (Cologne, 1639), which includes the phrase prima typographicae incunabula, "the first infancy of printing", a term to which he arbitrarily set an end, 1500, which still stands as a convention. The term came to denote the printed books themselves from the late seventeenth century. The plural is incunabula and the word is sometimes Anglicized to incunable. A former term is fifteener, referring to the fifteenth century.
The end date for identifying a book as an incunabulum is convenient, but was chosen arbitrarily. It does not reflect any notable developments in the printing process around the year 1500. Incunabula usually refers to the earliest printed books, completed at a time when some books were still being hand-copied. Some fastidious book-collectors of the fifteenth century eschewed printed books in their personal libraries.
The gradual spread of printing ensured that there was great variety in the texts chosen for printing and the styles in which they appeared. Many early typefaces were modelled on local forms of writing or derived from the various European forms of Gothic script, but there were also some derived from documentary scripts (such as most of Caxton's types), and, particularly in Italy, types modelled on handwritten scripts and pen based calligraphy.
Printers tended to congregate in urban centres where there were scholars, ecclesiastics, lawyers, nobles and professionals who formed their major customer-base. Standard works in Latin inherited from the medieval tradition formed the bulk of the earliest printing, but as books became cheaper, works in the various vernaculars (or translations of standard works) began to appear.
The British Library's Incunabula Short Title Catalogue now records over 29,000 titles, of which around 27,400 are incunabula editions (not works). Studies of incunabula began in the seventeenth century. Michel Maittaire (1667-1747) and Georg Wolfgang Panzer (1729-1805) arranged printed material chronologically in annals format, and in the first half of the nineteenth century, Ludwig Hain published, Repertorium bibliographicum — a checklist of incunabula arranged alphabetically by author: "Hain numbers" are still a reference point. Hain was expanded in subsequent editions, by W. Copinger and D. Reichling, but it is being superseded by the authoritative modern listing, a German catalogue, the Gesamtkatalog der Wiegendrucke, which has been under way since 1925 and is still being compiled at the Staatsbibliothek zu Berlin.
The largest collections, with the approximate numbers of incunabula held, include:
The number of printing cities stands at 282. These are situated in some 20 countries in terms of present-day boundaries. In descending order of the number of editions printed in each, these are: Italy, Germany, France, Netherlands, Switzerland, Spain, Belgium, England, Austria, Czechoslovakia, Portugal, Poland, Sweden, Denmark, Turkey, Croatia, Montenegro, Balearic Islands, Hungary, and Sicily.
The 18 languages that incunabula are printed in, in descending order, are: Latin, German, Italian, French, Dutch, Spanish, English, Hebrew, Catalan, Czech, Greek, Church Slavonic, Portuguese, Swedish, Breton, Danish, Frisian, and Sardinian.
Only about one edition in ten (i.e. just over 3000) has any illustrations, woodcuts or metalcuts. The 'commonest' incunabulum is Schedel's Nuremberg Chronicle ("Liber Chronicarum") of 1493, with c 1250 surviving copies (which is also the most heavily illustrated). Very many incunabula are unique, but on average about 18 copies survive of each. This makes the Gutenberg Bible, at 48 or 49 known copies, a rather common (though extremely valuable) edition.
Counting extant incunabula is complicated by the fact that most libraries consider a single volume of a multi-volume work as a separate item, as well as fragments or copies lacking more than half the total leaves. A complete incunabulum may consist of a slip, or up to ten volumes.
In terms of format, the 29,000 odd editions comprise: 2000 broadsides, 9000 folios, 15,000 quartos, 3000 octavos, 18 12mos, 230 16tos, 20 32tos, and 3 64tos.
ISTC at present cites 528 extant copies of books printed by Caxton, which together with 128 fragments makes 656 in total, though many are broadsides or very imperfect (incomplete).
Apart from migration to mainly North American and Japanese Universities, there has been remarkably little movement of incunabula in the last five centuries. None were printed in the Southern Hemisphere, and the latter appears to possess less than 2000 copies - i.e. about 97.75% remain north of the equator. However many incunabula are sold at auction or through the rare book trade every year.