Rosa Bonheur, the 19th-century French artist whose paintings of animals made her internationally renowned, made many unconventional choices in her lifetime. She famously obtained a special permit to wear men’s clothing, supported herself with her art, and favored the companionship of women. She was an unwed spinster by traditional standards — but she considered herself twice married, at least in a spiritual sense, to women. Remarkably enough, each union began with a portrait.

Bonheur was a teenager when she met her first partner. In 1836, when she was 14, her father was commissioned to paint a portrait of a local girl, Nathalie Micas. Almost immediately, Bonheur and Micas felt a strong affection toward one another, and they eventually decided to spend their lives together. Micas supported Bonheur as she built her illustrious career, largely tending to household affairs so that Bonheur could focus on painting. Their partnership continued for 50 years, until 1889.

In June of that year, Micas died, and Bonheur was heartbroken. A few months passed before Bonheur met a young American portrait painter, Anna Klumpke. She was acting as an interpreter for an American businessman who had given Bonheur horses, one of her favorite subjects.

For Klumpke, meeting the artist was a childhood dream. After all, she grew up playing with a beloved Rosa Bonheur doll — a porcelain-faced model of the artist, popular in the United States during the mid-1800s — and Bonheur had unknowingly jump-started the American’s artistic career. Decades earlier, when Klumpke moved with her mother and three sisters to Paris, Bonheur’s “Plowing in the Nivernais” (1849) caught the budding artist’s eye in a museum, inspiring her to request permission to copy it in the galleries.

“How often I lingered before the picture,” Klumpke recalled toward the end of her life, in Memoirs of an Artist (1940). “Was it not, indeed, in copying that picture that there came to me a revelation of my artistic vocation? That picture became to me a talisman.” Klumpke sold her copy to a fellow American, for 1,000 francs, allowing her to completely cover her first year’s tuition at private Parisian art school, Académie Julian. (By comparison, Bonheur sold the original painting to the French government for 3,000 francs, after exhibiting it at the Paris Salon.)

After their first meeting, Bonheur and Klumpke remained pen-pals for almost a decade. Klumpke returned to the US, settling in Boston where she taught painting classes, exhibited her work, and received numerous portrait commissions, including one of suffragist Elizabeth Cady Stanton that hangs at the National Portrait Gallery. In her letters, Bonheur called Klumpke a “sister of the brush.”

Something changed in 1898, when Klumpke asked for permission to paint Bonheur’s portrait. Bonheur agreed to the request immediately, and an ecstatic Klumpke boarded a ship to Paris. She arrived at Bonheur’s home on June 11, 1898, and began painting the portrait five days later. Little did she know that the process would take months, with Bonheur deliberately withholding sittings to lengthen Klumpke’s stay.

As one of her stalling techniques, Bonheur gave Klumpke a tour of her medals and awards, describing each and lamenting that none came from England or the US. Klumpke took the hint and, fashioning herself an American ambassador of sorts, wove Bonheur a crown of “true laurel, the stuff of Apollo’s crown.” Klumpke inscribed the crown’s ribbon with the dates 1822-1922 — the dates of Bonheur’s life were she to live to 100. Bonheur was incredibly moved, immediately declaring that she wanted to be buried with the crown, and placed it for safekeeping on the antlers of a sculptured stag in her studio.

Bonheur eventually ran out of stalling tactics, though, and Klumpke completed her nearly life-sized academic portrait. It depicts the accomplished Bonheur, haloed by short, silvery hair, looking out from her studio directly towards her portraitist — who, proudly and prominently, signed the lower right of the canvas. Behind Bonheur is a small canvas study for “La Foulaison,” a large-scale work Bonheur intended to show at the Universal Exposition of 1900, but sadly never completed. The portrait was finished just in time to participate in the Carnegie International exhibition in Pittsburgh in November 1898.

With nothing left to keep Klumpke at Bonheur’s château, Bonheur came clean about her feelings, according to Rosa Bonheur: Sa Vie, Son Oeuvre, a biography that Klumpke later wrote. Bonheur dramatically proposed “a divine marriage of two souls” to the American artist, 34 years her junior. “Since we’re both alone in life,” Bonheur is quoted as writing to Klumpke’s disapproving mother, “wouldn’t it be more pleasant for us to lead a happy life painting together, all the while remaining independent?”

Bonheur invited Klumpke to share her life and home, offering her the opportunity to write the French animalière’s biography and handle her estate. “Friendship … is better sometimes than passing love,” Bonheur told Klumpke. “Friendship of the soul may become a divine affection; it is superior to family relations, and such friendship will last beyond our earthly existence.” Despite her mother’s protests, Klumpke agreed. It is not known whether the relationship was romantic, since neither Rosa Bonheur: Sa Vie, Son Oeuvre nor Klumpke’s own memoirs explicitly mentions whether they were lovers.

As it turned out, the earthly duration of the “marriage” was short. Bonheur died in 1899, but Klumpke made the last chapter of the French artist’s life a happy one. Klumpke, in turn, was left with a portrait, among other things. She kept it until 1922, the date she had inscribed on the laurel wreath, and then gifted it to the Metropolitan Museum of Art. She stated that her donation was “in honor of Rosa Bonheur’s centenary and in memory of the great friendship in which she held me and all America in general.” The same collection contained Bonheur’s “The Horse Fair,” which was given to the museum by Cornelius Vanderbilt during the height of Bonheur’s career.

The donation seems a fitting tribute to the partnership between the two women. When Bonheur first proposed partnership to Klumpke, she promised she would support the younger artist’s ambition and propel her forward — turning her into “a second Rosa Bonheur.” But the French painter added: “That doesn’t mean that you’ll do another ‘Horse Fair.’ I know full well that you’ll always be Anna Klumpke, with your own personality. But, with my methods, you’ll go a step higher.” Succeed Klumpke did, to the point that she could place her artwork in the collection of the same illustrious museum as Bonheur.

Klumpke outlived Bonheur by 43 years, spending the next couple decades at Bonheur’s Château de By. Incidentally, she wasn’t too far from Paris, where another avant-garde female couple, Gertrude Stein and Alice B. Toklas, lived together. In 1899, she opened the Rosa Bonheur Memorial Art School, which was open to women artists of all nationalities. She also arranged for Bonheur exhibitions and the gift of 50 Bonheur studies to the French government. On the 25th anniversary of Bonheur’s death, she established the Rosa Bonheur Museum (which will reopen to the public during the spring of this year).

According to Memoirs of An Artist, “Miss Klumpke’s constant aim was to render the recognition of Rosa Bonheur’s genius as a practical aid and encouragement to young artists.” Klumpke’s dedication to Bonheur’s legacy — an effort she presented as her life’s work — also paid tribute to the elder painter’s devotion to supporting fellow women artists. “I am proud to be a woman, and to the end of my years I shall uphold the rights of women in all professional work and in all honorable endeavors,” Bonheur once said to Klumpke. “It belongs to us women to elevate the human race.”