John Dee and the Library at Mortlake, the Richest in England

In the second half of the sixteenth century, in a village on the Thames west of London, stood one of the richest book collections in England. It belonged to John Dee (1527-1608 or 1609), mathematician, astrologer, occasional adviser to Elizabeth I and student of everything then called natural philosophy. The family house at Mortlake, which had belonged to his mother, gradually became a place of study visited by navigators, courtiers and foreign scholars, drawn by the volumes and instruments Dee had gathered there.

A Plan for a National Library

As early as 1556 Dee petitioned Queen Mary Tudor to rescue the manuscripts scattered by the dissolution of the monasteries, ordered by Henry VIII in the 1530s. He proposed to seek out the best copies at home and abroad, to have them transcribed and to keep them in a royal library. The plan came to nothing, but it reveals the method Dee later applied to himself: buying, copying and salvaging from the ruins of the old monastic libraries.

Many of the medieval codices at Mortlake came from those dispersed collections. Dee was particularly keen on the works of Roger Bacon, whom he regarded as a forerunner, together with treatises on astronomy, optics, alchemy and geography. Next to the manuscripts were printed editions bought during his stays in Louvain, Paris and Antwerp, where the young Dee had studied and formed ties with continental cartographers and mathematicians.

The Catalogue of 1583

The size of the collection is known thanks to a catalogue drawn up by Dee himself and dated 6 September 1583, a few weeks before he left for Central Europe with Edward Kelley and the Polish nobleman Albert Łaski. The list records thousands of titles, both printed books and manuscripts; modern scholars have produced a critical edition that allows the owner's interests to be reconstructed entry by entry.

The catalogue shows an encyclopaedic library rather than an occult one. Mathematics, astronomy, medicine and history dominate; magic and alchemy are present, but as part of a unified knowledge in which number, light and the heavens explained one another. It is the same horizon as the Monas hieroglyphica, published by Dee in Antwerp in 1564, and of the mathematical preface he wrote in 1570 for the first English translation of Euclid.

Plunder and Dispersal

When Dee returned to England in 1589, he found his house violated. Books and instruments had been taken or damaged during his absence; in later writings he lamented the loss of works he would never recover. The exact causes of the plunder remain unclear, and the accounts of a mob hostile to the «conjurer» are late and uncertain.

What survived was scattered further after his death. Today the volumes that belonged to Dee are identified by their marginal notes and marks of ownership, and they are spread across dozens of libraries. The largest group, about a hundred books, is kept at the Royal College of Physicians in London; others are in Oxford, in Cambridge and at the British Library.

The Mortlake library no longer exists as a whole, but its catalogue remains one of the most eloquent documents of English Renaissance culture. It shows how, for a sixteenth-century man, the boundary between science, philosophy and the occult arts ran through the same shelves, and how a passion for rare books could coexist with the search for a wisdom believed to be lost.