Encyclopedias have progressed from the beginning of history in written form, through medieval and modern times in print, and most recently, displayed on computer and distributed via computer networks.
Western encyclopedias
Ancient times
Encyclopedias have existed for around 2,000 years, although even older glossaries such as the Babylonian Urra=hubullu and the ancient Chinese Erya are also sometimes described as "encyclopedias".
Marcus Terentius Varro
Marcus Terentius Varro (; 116 BC – 27 BC) was an ancient Roman scholar and writer.
His Nine Books of Disciplines became a model for later encyclopedists, especially Pliny the Elder. The most noteworthy portion of the Nine Books of Disciplines is its use of the liberal arts as organizing principles. Varro decided to focus on identifying nine of these arts: grammar, rhetoric, logic, arithmetic, geometry, astronomy, musical theory, medicine, and architecture. Using Varro's list, subsequent writers defined the seven classical "liberal arts of the medieval schools".
Pliny the Elder
The earliest encyclopedic work to have survived to modern times is the Naturalis Historia of Pliny the Elder, a Roman statesman living in the 1st century AD. He compiled a work of 37 chapters covering natural history, architecture, medicine, geography, geology, and all aspects of the world around him. He stated in the preface that he had compiled 20,000 facts from 2000 works by over 200 authors, and added many others from his own experience. The work was published around AD 77–79, although he probably never finished proofing the work before his death in the eruption of Vesuvius in AD 79.
My subject is a barren one – the world of nature, or in other words life; and that subject in its least elevated department, and employing either rustic terms or foreign, many barbarian words that actually have to be introduced with an apology. Moreover, the path is not a beaten highway of authorship, nor one in which the mind is eager to range: there is not one of us who has made the same venture, nor yet one Greek who has tackled single-handed all departments of the subject.
He also elaborates on the difficulties of writing such a work:
It is a difficult task to give novelty to what is old, authority to what is new, brilliance to the common-place, light to the obscure, attraction to the stale, credibility to the doubtful, but nature to all things and all her properties to nature.
This work became very popular in Antiquity, and survived, with many copies being made and distributed in the western world. It was one of the first classical manuscripts to be printed in 1470, and has remained popular ever since as a source of information on the Roman world, and especially Roman art, Roman technology and Roman engineering. It is also a recognised source for medicine, art, mineralogy, zoology, botany, geology and many other topics not discussed by other classical authors. Among many interesting entries are those for the elephant and the murex snail, the much sought-after source of Tyrian purple dye.
Although his work has been criticized for the lack of candor in checking the "facts", some of his text has been confirmed by recent research, like the spectacular remains of Roman gold mines in Spain, especially at Las Médulas, which Pliny probably saw in operation while a Procurator there a few years before he compiled the encyclopedia. Although many of the mining methods are now redundant, such as hushing and fire-setting, it is Pliny who recorded them for posterity, thereby helping us understand their importance in a modern context. Pliny makes clear the fact in the preface to his work that he had checked his facts by reading and comparing the works of others, as well as referring to them by name. Many such books are now lost works and remembered only by his references, much like the lost sources mentioned in the work of Vitruvius a century earlier.
Middle Ages
The work De nuptiis Mercurii et Philologiae ("About the wedding of Mercury and Philologia") written by Martianus Capella (4th-5th century) was very influential on the successive medieval encyclopedias. It consists in a complete encyclopedia of classical erudition. It firstly introduced the division and classification of the seven liberal arts (trivium and quadrivium), followed by many successive works along the Middle Ages.
The first Christian encyclopedia was the Institutiones divinarum et saecularium litterarum of Cassiodorus (543-560), which were divided in two parts: the first one dealt with Christian Divinity; the second one described the seven liberal arts.