Lovers to friends: the intimate story of Van Gogh’s sister-in-law and the artist Isaac Israëls – The Art Newspaper

​For well over a century it was a family secret: Vincent van Gogh’s sister-in-law, Jo Bonger, had a short relationship with the Dutch Impressionist painter Isaac Israëls. Amsterdam’s Van Gogh Museum has just published the surviving 103 letters sent by Israëls to Bonger, and is presenting a focussed exhibition about their “intimate friendship”.

​Captivated by Vincent: The Intimate Friendship of Jo van Gogh-Bonger and Isaac Israëls (until 25 January 2026) is not just about the relationship, but equally importantly it covers its impact of Van Gogh’s art on Israëls. In a surprising move, the latter depicted some of Van Gogh’s most important paintings in the backgrounds of a series of portraits.

Israëls vividly described this practice as “Vincenting”. ​Twelve of these 17 portraits have been brought together for the very first time, while a five remain in unknown private collections.

​Isaac Israëls (1865–1934), the son of the distinguished artist Jozef Israëls (1824-1911), first met Bonger briefly in September 1889 through her newly-married husband Theo van Gogh, Vincent’s brother. Vincent then died by suicide in July 1890 and Theo in January 1891, probably from syphilis. It was not until 1895 that Bonger and Israëls got to know each other well, when he was aged 29 and she 32.

​Their relationship became “intimate” later that year. As the Van Gogh Museum researcher Hans Luijten, the author of the definitive biography of Bonger, explains, it was briefly “a physical relationship”. Bonger confided in her diary on 3 November: “It was just an impulse, we played with fire.” She then added: “But there’s no trifling with love.” The following three lines were physically cut out of her diary, either by herself or her son. What she removed has been lost forever.

Bonger fell in love with Israëls, and although he harboured similar feelings, he was reluctant to make a commitment, instead wanting to retain his independence. In August 1895 Israëls wrote to her that “I’m adrift at sea buffeted by several hurricanes”. She, on her side, felt uneasy about the intimacy, mainly because of concerns about the impact on her five-year-old son Vincent (named after the artist). It was an uneasy relationship.

​In August 1896 Israëls sent a letter from the seaside, mostly obscured with a sketch of a young woman on the beach at Scheveningen, just outside The Hague. Luijten suggests that Israëls was implying he was perhaps a better artist than a writer.

His romantic relationship with Bonger ended in the late summer of 1897, two years after it had begun. Bonger seems to have made the decision, although Israëls made little effort to resist it. In 1901 Bonger went on to marry the artist Johan Cohen Gosschalk, but he suffered ill health and died in 1912.

​Bonger and Israëls got in contact again after Gosschalk’s death. In 1914 Bonger’s 24-year-old son Vincent and Israëls both happened to be in London at the same time. It was then that Israëls painted Vincent reading a newspaper in a café in Hyde Park. This picture was given to Bonger who, in exchange, gave Israëls a Van Gogh painting, most likely the Olive Grove (September 1889, now private collection, Zurich). During the period between 1915 and 1920 a deep friendship developed between Israëls and Bonger.

Vincenting

​In the winter of 1915-16 Israëls asked if he could borrow three of Van Gogh’s greatest paintings: The Yellow House (September 1888), Van Gogh’s Bedroom (October 1888) and the Sunflowers with a yellow background (it was either the August 1888 first version, now at London’s National Gallery, or a similar January 1889 one, now at the Van Gogh Museum). The three paintings were kept for different periods, but all were returned by 1920.

​Israëls incorporated the Van Gogh compositions in the backgrounds of 16 painted portraits and one drawing. Writing to Bonger in February 1916 he invented a term to describe the insertion of Van Gogh paintings in his own work. “I’m still very busy Vincenten (Vincenting),” he wrote.

In two of these paintings a bare-breasted model is portrayed, while In another the woman is smoking. ​The Van Gogh painting which figured most frequently was the Sunflowers, which must have suffered from tobacco grime during its years with Israëls, since he himself was a heavy smoker. These pictures are also interesting in showing how the Sunflowers was then framed, in a simple white frame.

​With Girl Reading on a Sofa (1915-16), Israëls included two more of the Van Gogh paintings that he had borrowed: part of The Yellow House can be seen on the left and Van Gogh’s Bedroom on the right.

​All of the “Vincenting” paintings are of female figures (either anonymous models or friends), with a single exception. He once painted his cousin Isaac Cohen, a law professor, with his wife Jacqueline.

​So why did Israëls include Van Gogh paintings in portraits which appear to have little to do with the great artist? Luijten suggests that the Van Goghs were added “to make the figures and objects in the foreground more prominent by emphatically contrasting the colours through using, for example, bright red, blue and purple”. He adds, tellingly, that Israëls also wanted to make the works ”more appealing by linking them to Van Gogh”, who had already become famous. In other words, the works became more marketable.

​Interestingly, the borrowed paintings seem to have exerted little influence on the technique of Israëls. By this time, then in his early fifties, Israëls painted in a loose style and is often referred to as a “Dutch Impressionist”.

​On New Year’s Day 1924, the year before Bonger’s death, Israëls praised her decades-long loyalty: “You really are a true friend,” he wrote. This would be the last known letter he sent to her—and sadly none of Bonger’s letters to him survive.

​Bonger died on 2 September 1925, aged 62. Shortly afterwards, her son, Vincent, commissioned Israëls to paint a final portrait of his mother. In the background Israëls added a fuzzy picture, which appears to represent the strong blue sky of Van Gogh’s The Yellow House. Although he made a series of portraits of Bonger, this was the only one in which he included a Van Gogh.

Israëls died in 1934. He never married, although from the 1920s he had a long-term relationship with Sophie de Vries, who lived with him and became his muse.

Martin Bailey is a leading Van Gogh specialist and special correspondent for The Art Newspaper. He has curated exhibitions at the Barbican Art Gallery, Compton Verney/National Gallery of Scotland and Tate Britain.

Martin has written a number of bestselling books on Van Gogh’s years in France: The Sunflowers Are Mine: The Story of Van Gogh’s Masterpiece (Frances Lincoln 2013, UK and US), Studio of the South: Van Gogh in Provence (Frances Lincoln 2016, UK and US), Starry Night: Van Gogh at the Asylum (White Lion Publishing 2018, UK and US) and Van Gogh’s Finale: Auvers and the Artist’s Rise to Fame (Frances Lincoln 2021, UK and US). The Sunflowers are Mine (2024, UK and US) and Van Gogh’s Finale (2024, UK and US) are also now available in a more compact paperback format.

His other recent books include Living with Vincent van Gogh: The Homes & Landscapes that shaped the Artist (White Lion Publishing 2019, UK and US), which provides an overview of the artist’s life. The Illustrated Provence Letters of Van Gogh has been reissued (Batsford 2021, UK and US). My Friend Van Gogh/Emile Bernard provides the first English translation of Bernard’s writings on Van Gogh (David Zwirner Books 2023, UKand US).

To contact Martin Bailey, please email vangogh@theartnewspaper.com

Please note that he does not undertake authentications.

Explore all of Martin’s adventures with Van Gogh here