There’s a new addition to the list of known works by famed Baroque painter Artemisia Gentileschi (1593–1654), and it’s coming up for auction tonight at Sotheby’s New York. The dramatically lit canvas, Saint Sebastian Tended by Irene, undeniably bears the hallmarks of the Old Master’s work, with its Caravaggesque lighting and focus on female agency, the wounded saint overshadowed by the two women ministering to his wounds.

The auction house is expecting the painting to sell for $400,000–600,000, potentially an order of magnitude higher than when it last sold, at Bonhams London, for £40,000 ($62,804) on December 3, 2014. At the time, it was attributed to a “Follower of Caravaggio,” but the anonymous buyer already had a suspicion that the painting’s true authorship was far more interesting, as the potential handiwork of Gentileschi.

Edoardo Roberti, a senior specialist in the Old Master paintings department at Sotheby’s, had the same hunch, and turned to experts to confirm the attribution. Nicola Spinosa, the former head of the Capodimonte Museum in Naples, and Giuseppe Porzio, an art history professor at the University of Naples, both examined the work and independently confirmed it was indeed by Gentileschi’s hand, likely made after she moved to Naples in 1630.

“The subject matter of Artemisia’s paintings is nearly always based around female empowerment,” Roberti told artnet News. “Here, it doesn’t really focus on Sebastian. It focuses on these two women.”

Victoria Beckham with Artemisia Gentileschi’s Saint Sebastian Tended By Irene at the exhibition for “The Female Triumphant” at Sotheby’s New York. Photo courtesy of Tom Newton.

The painting is one of 21 works by female Old Masters spotlighted in tonight’s “The Master Paintings Evening Sale” in a special gallery christened “The Female Triumphant.” (The works, by the likes of Elisabeth Louise Vigée Le Brun and Angelika Kauffmann, were touted by none other than former Spice Girl Victoria Beckham at a special auction preview last week.)

Over the past five years, Gentileschi’s market has been on a steep upward trajectory. In 2014, Gentileschi’s Bathsheba at Her Bath sold for a record £602,500 ($945,988) at Sotheby’s London, well over its high estimate of £300,000 ($314,021). The artist’s market has not looked back since, with her two most recent sales both shattering the $2 million barrier. 

Artemisia Gentileschi (1593–1654 or later), Self-Portrait as Saint Catherine of Alexandria (around 1615-17). Copyright The National Gallery, London.

Roberti hopes that Saint Sebastian will follow in these paintings’ footsteps by far exceeding expectations. “It’s an inviting estimate,” he said, adding that he has no doubts about the painting’s new attribution. “So many Old Master paintings are not documented and are not signed, but one can come to the consensus of the attribution on the basis of style and recognizing the handwriting of that artist.”

Spinosa, one of the experts Roberti consulted, specifically cited the painting’s resemblance to other works by the artist, particularly the play of light and shadow in her canvases Annunciation, in the Capodimonte collection, and Judith and Her Maidservant, now owned by the Detroit Institute of Arts.

Artemisia Gentileschi, Annunciation. Courtesy of the Capodimonte Museum, Naples.

“Followers of Caravaggio could use light in quite a dramatic and violent way,” noted Roberti. “Here, the light is soft and it really serves to bring the contour of the Sebastian’s wounded body and this wonderful interaction between the two women on the left.”

The canvas also reflects Gentileschi’s evolution as an artist, particularly as she moved throughout Italy. The artist “was able to assimilate her surroundings in a remarkable way,” Roberti said. “I wonder if this was because as an artist who very much paid her way in life, she had to adjust to local tastes to be commercially successful.”

Artemisia Gentileschi, Judith and Her Maidservant. Courtesy of the Detroit Institute of Arts.

Of course, today, Gentileschi’s fierce, proto-feminist canvases are very much in line with the taste of the day. As a new addition to her oeuvre, Saint Sebastian seems likely to attract considerable attention at tomorrow’s sale—recent works to market have been snapped up by institutions, such as Self-Portrait as a Lute Player (circa 1616–18) acquired by the Wadsworth Atheneum Museum of Art in Hartford, Connecticut in 2014, or the record-setting Saint Catherine, which later landed at London’s National Gallery for the hefty price of £3.6 million ($4.7 million).

Regardless of who winds up owning this newly recognized painting, said Roberti, “it’s such a privilege to be involved in giving a painting its correct status and letting it enjoy the prestige it should have had all along.”