After Newton and Babbage, today we look at the surviving images of the astronomer Johannes Kepler (1571–1630). Kepler was born the son of an innkeeper’s daughter and a mercenary, who deserted his family when Johannes was just five years old. This is not the environment in which parents have portraits painted of their children. In fact, there are very few portraits of Johannes Kepler at all and we don’t know the source of most of them and several are clearly produced posthumously and we don’t know is they’re are based on an existing image or are just the artist’s imagination.
There is one contemporary painting by the German artist Hans van Aachen (1552–1615), a leading representative of Norther Mannerism. It is described as the portrait of a young man thought to be Johannes Kepler but the attribution is not certain.
There is another portrait in the Galleria degli Uffizi in Florence, which is labelled Johannes Keplerus, but neither the artist nor when it was painted is known. It is, however, attributed to the seventeenth century.
There is a nineteenth century engraved portrait by the English watercolourist and architectural draughtsman Frederick Mackenzie (1787–1854), which is now in the Smithsonian Dibner Library of the History of Science and Technology. The caption says From a Picture in the Collection of Godefrey Kraemer Merchant of Ratisbon. Ratisbon is an English alternative name for Regensburg the city in which Kepler died and was buried.
The Dibner also has a copy of the Uffizi Kepler engraving, as well as an undated engraved portrait in profile.
Also in the Dibner is an engraving of a portrait of Johannes Kepler from a 1620 painting that was given to the Strasbourg Library in 1627, artist unknown. There is a painting from 1910 based on the engraving in the Kepler-Museum in Weil der Stadt, Kepler’s birth-place, by the German painter August Köhler (1881–1964).
Amongst all this doubt about the various portraits of Kepler the most surprising is the fact that a very impressive portrait in the possession of a Benedictine monastery in Kremsmünster, Austria, that was thought to be Kepler painted in 1610 is now thought to have been first painted in the nineteenth century and probably not Kepler at all. I myself have used it several time on Kepler posts in the past but no longer.
Addenda 31.12.2025
In the comments, Laura quite correctly drew my attention to the fact that I hadn’t included the wedding portraits of Barbara and Johannes Kepler. I couldn’t find any information on these portraits anywhere on the Internet so I asked Professor Aviva Rothman, Inaugural Dean’s Associate Professor and Director of Graduate Studies at Case Western Reserve University, who is a Kepler expert and currently writing a new biography of Kepler. She directed my attention to the paper The Fate of Kepler’s Handwritten Heritage by Irina Tunkina in Culture and Cosmos Vol. 25, Spring/Summer & Autumn/Winter 2021. Tunkina writes:
In 1876 the Pulkovo Observatory acquired the family treasures from the direct descendants of Kepler’s first wife, Barbara Müller von Mülek (the sisters Emma, Ottilie and Augusta Schnieber) for 400 marks. These were added to the collection.53 There was a pair of miniature oil portraitsof Johannes and Barbara Kepler from 1597, made during their lifetime
(Figures 1–2),
The Renaissance Mathematicus 