Rembrandt Harmensz Van Rijn (Dutch, 1606-1669), “Portrait of a Woman,” 1634, oil on panel.

Visitors to the Speed Art Museum have been fascinated for years by the museum’s Rembrandt, “Portrait of a Woman,” whose identity has remained one of history’s mysteries. Now, the museum would like to introduce the world to Marretje Cornelisdr van Grotewal.

Since the acquisition of “Portrait of a Woman,” museumgoers have been fascinated by this transfixing portrait painted by one of the most famous Dutch artists of the Seventeenth Century, Rembrandt Harmensz Van Rijn. The painting is currently on view in London’s Dulwich Picture Gallery, in an exhibition commemorating the 400th year of Rembrandt’s birthday. Curator Jaap Van der Veen discovered the subject’s identity while researching materials for the exhibition.

The companion portrait to this painting, “Portrait of a Bearded Man in a Wide-Brimmed Hat,” 1633, depicts this woman’s husband, Pieter Sijen. The paintings remained together until 1960 when they were sold separately at auction in New York City. The woman’s portrait was purchased by the Speed in 1977, and the Norton Simon Art Foundation purchased the husband’s portrait in the same year.

In his investigation, Van der Veen first looked into the relationship between art dealer Hendrick Uylenburch and Peter Sijen. He found that in 1639 Sijen invested in Uylenburch’s business and the two continued to have a business relationship for years. Both men were also members of the Mennonite community, a religious group that is known to favor plain living and plain dress, much like the woman’s dress depicted in the Rembrandt painting.

Rembrandt was connected to Uylenburch, both in his professional and personal life. He worked for and lived with the art dealer for four years until he married Uylenburch’s niece Saskia Uylenburch in 1634.

There were several other clues that contributed to Van der Veen’s conclusions. After researching historical documents, a 1702 inventory described a pair of portraits by Rembrandt of the ancestors of Peter Pietersz Sijen, the son of the man in the portrait. The ages of the subjects written on the paintings also corresponded with the ages of Marretje Cornelisdr van Grotewal and Pieter Sijen, thus supporting Van der Veen’s findings.

“Portrait of a Woman” is often admired for its excellent condition due to the fact that it was never subjected to overly harsh cleaning, which so often results in the rubbing away of paint layers. “We are very excited about this discovery. It is truly gratifying to put a name with the face that has become such a highlight of the museum’s collection,” said museum director Peter Morrin.

The Speed Art Museum is at 2035 South Third Street. For information, 502-634-2700 or www.speedmuseum.org.