Nikolaus Joseph von Jacquin's letters to Linnaeus

Nikolaus Joseph Baron von Jacquin: A botanist, an 18th century collector and a pen pal to Linnaeus

Published on 5th March 2021

Nikolaus Joseph von Jacquin's signature

This month’s treasure is not a single object, but a collection of letters written to Linnaeus by Nikolaus* Joseph Baron von Jacquin. I have chosen this collection of almost 100 letters from the perspective of someone who has spent a significant amount of her time in lockdown cleaning up metadata for the Society’s Online Collections. I have been working primarily on Linnaeus’ correspondence, which has involved checking the records of over 4,000 letters. The work can, admittedly, become a little monotonous, not only for having to correct hundreds of metadata fields, but also for looking at thousands of letters, which are page after page of barely legible handwriting, often in languages I can’t understand. So when Jacquin’s letters appeared, peppered with plates and sketches, it was a pleasure to the eye. They broke through the visual monotony. Also, from a collections management perspective, the more I looked into these letters and all of the associated plates, the more I realised that these letters present a bit of a challenge.

Detail of gate at Schoenbrunn Palace
Detail of Schönbrunn Palace, visited by Andrea this time last year.

Nikolaus Joseph Baron von Jacquin (1727-1817) was a Dutch-born Austrian botanist. He studied medicine and botany at Leiden University. He continued his studies in Paris, and then in Vienna. He maintained a keen interest in botany and was a champion of the new Linnaean system. Jacquin was a friend of Gerard van Swieten, who was physician to the Empress Maria Theresa, and advisor on the planning of the gardens at Schönbrunn Palace. Swieten recommended that Emperor Franz I commission an expedition to the Caribbean to collect tropical plants to fill the conservatories at Schönbrunn, and it was Jacquin who was selected for the expedition (1755-1759).

Upon his return, Jacquin published Enumeratio Systematica Plantarum (1760), which garnered the attention of Linnaeus and soon, they were firm correspondents. Jacquin published several botanical works throughout his career and became the Director of the botanic gardens at the University of Vienna, and supervised the gardens at Schönbrunn palace. He was made Baron in 1806.

Plant specimens sent to Linnaeus from Jacquin
Plant specimens sent to Linnaeus (L3025)

As mentioned, Jacquin included many plates, and even the occasional specimen (L3025) or sketch (L4928 & L5432) in his correspondence to Linnaeus. The plates, both coloured and black & white engravings, came mainly from two of Jacquin’s publications: Hortus Botanicus Vindobonensis (1770-1776) and Florae Austriacae (1773-1778), both of which are held at the Society. According to some of his letters, Jacquin was sending these plates ahead of publication for Linnaeus' opinions. This plate of Crataegus punctata (Tab.28 from H. Bot. Vind.), for example, was sent to Linnaeus a few times, and Jacquin seemed eager to discuss it (see summary). Sometimes, however, I think he was just including these plates for Linnaeus’ reference. It is also wonderful to see the evolution of their relationship within these letters – with Jacquin almost in wide-eyed admiration of Linnaeus at the beginning, ready to be taught by the master (L2617), to a change in Jacquin's confidence, who grew to debate with and overrule Linnaeus (L4928).

Crataegus punctata
Crataegus punctata (L4548)

The challenge for us as collections managers is that the letters mention many plates that are no longer in the correspondence collection (e.g. L5137), and many of the plates we do have in the collection have been grouped together, separated from the letters with which they arrived to Linnaeus. Fortunately, most of Jacquin’s letters have been transcribed and summarised in English through the Linnaean Correspondence Project, and the results can be found on Uppsala University Library’s ALVIN portal. We hope that one day we will integrate these transcriptions and summaries with our own records, and use them to marry up the plates and letters once again.

Andrea Deneau, Digital Assets Manager

*Nikolaus is the spelling most commonly found. The Linnaean Correspondence Project, and, as a consequence, our Online Collections records use the spelling ‘Nicolaus’.


BHL, ‘Hortus botanicus vindobonensis…’,, accessed 25/02/2021.

JSTOR, ‘Jacquin, Nicolaus (Nicolaas) Joseph von (1727-1817)’,, accessed 25/02/2021.

The Linnean Society of London – Online Collections,, accessed 25/02/2021.

Uppsala University Library – ALVIN,, accessed 25/02/2021.

Wikipedia, ‘Nikolaus Joseph von Jacquin’,, accessed 25/02/2021.