A portrait of a young woman by Gustav Klimt that was long believed to be lost was sold at an auction in Vienna on Wednesday for $32 million.

The Austrian modernist artist started work on the "Portrait of Fräulein Lieser" in 1917, the year before he died, and it is one of his last works. Bidding started at 28 million euros, and the sale price was at the lower end of an expected range of 30-50 million euros.

The painting went to a bidder from Hong Kong, who wasn't identified.

The Im Kinsky auction house said that "a painting of such rarity, artistic significance, and value has not been available on the art market in Central Europe for decades."

The intensely colored painting was auctioned on behalf of the current owners, Austrian private citizens whose names weren't released, and the legal heirs of Adolf and Henriette Lieser, members of a wealthy Jewish family in Vienna who were clients of Klimt, one of whom is believed to have commissioned the painting. Some experts believe the lady in the painting could have been one of the several women in the family. Still, it is unclear who "Fräulein Lieser" is exactly.

The auction house said the woman in the portrait visited Klimt's studio nine times to pose for the artist.

Klimt left the painting, with small parts unfinished, in his studio when he died of a stroke in early 1918. It was then given to the family who had commissioned it, according to the auction house.

The Jewish family fled Austria after 1930 and lost most of their possessions.

It's unclear exactly what happened to the painting between 1925 and the 1960s, a period that includes the Nazi dictatorship. Austria was annexed by Nazi Germany in 1938. One of the only clues is a black-and-white photo of the portrait likely taken in 1925 that came with a note reading, "1925 in possession of Mrs. Lieser, IV, Argentinierstrasse 20." There was no other proof of the painting's existence until it resurfaced early in 2024, having apparently been secretly owned by a private collector for decades.

The auction house says there is no evidence that the painting was confiscated during the Nazi period, but also no proof that it wasn't. It ended up with the current owners through three successive inheritances.

Ernst Ploil, co-chief executive of the Im Kinsky auction house, said, "Every form of taking away during the Nazi time has to be treated as unlawful," according to the New York Times. 

In view of the uncertainty, an agreement was drawn up with the current owners and the Liesers' heirs to go forward with the sale under the Washington Principles, which were drafted in 1998 to assist in resolving issues related to returning Nazi-confiscated art.

The auction house said it was very happy with Wednesday's result.

The sale price was an art auction record for Austria. The highest price previously paid at an auction in the country was just over 7 million euros for a work by Frans Francken the Younger in 2010.

—Caitlin O'Kane contributed to this report.