A painting by Thomas Couture that was looted by the Nazis from a Jewish French politician and resistance figure -- who was later executed during World War II -- was returned to the man's heirs Tuesday.

“Portrait of a Seated Young Woman” by Couture, the 19th-century French painter, was in the possession of Georges Mandel at the height of the war. Mandel was executed by French fascists near Paris in 1944 and, after the war, the painting was reported to have been stolen.

Forgotten for decades, the painting was eventually unearthed in the art trove of late collector Cornelius Gutlitt, who was under investigation for a tax case by German authorities in 2012.

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The reclusive Bavarian collector inherited much of a 1,500-piece collection from his father, Hildebrand Gurlitt, an art dealer who traded in works confiscated by the Nazis. Many are thought to have been looted from their original Jewish owners, but provenance research has been slow and only a few have been resituated.

Government Commissioner for Culture and the Media Monika Gruetters, right, overhands the painting 'Portrait of a Seated Young Woman' by Thomas Couture to Franz Rainer Wolfgang Joachim Kleinertz, left, and Maria de las Mercedes Estrada, second from left, heirs of Jewish French politician Georges Mandel, during a restitution ceremony in Berlin. (AP Photo/Markus Schreiber)

Government Commissioner for Culture and the Media Monika Gruetters, right, overhands the painting 'Portrait of a Seated Young Woman' by Thomas Couture to Franz Rainer Wolfgang Joachim Kleinertz, left, and Maria de las Mercedes Estrada, second from left, heirs of Jewish French politician Georges Mandel, during a restitution ceremony in Berlin. (AP Photo/Markus Schreiber)

The Kunstmuseum Bern inherited the younger Gurlitt’s collection – which included pieces by masters such as Monet, Gauguin, Renoir and Picasso – when he died in 2014. Some 500 works were left in the hands of a German government task force to research their origins.

According to AFP, experts determined two years ago the Couture painting had been looted from Mandel – mostly relying on a small hole in the canvas as evidence. Mandel’s lover had cited the hole above the seated woman’s torso when she reported it stolen.

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German Culture Minister Monika Gruetters presented the work to family members of Mandel in a ceremony Tuesday at the Martin Gropius Bau museum in Berlin.

Franz Rainer Wolfgang Joachim Kleinertz, left, and Maria de las Mercedes Estrada, right, heirs of Jewish French politician Georges Mandel stand next to the painting 'Portrait of a Seated Young Woman' by Thomas Couture during a restitution ceremony in Berlin. (AP Photo/Markus Schreiber)

Franz Rainer Wolfgang Joachim Kleinertz, left, and Maria de las Mercedes Estrada, right, heirs of Jewish French politician Georges Mandel stand next to the painting 'Portrait of a Seated Young Woman' by Thomas Couture during a restitution ceremony in Berlin. (AP Photo/Markus Schreiber)

She called the Couture painting’s return “a moving conclusion to the exhibitions of the Gurlitt trove,” AFP reported.

“In this way, we can inform the public about the fate of the Jewish politician Georges Mandel, who was persecuted and imprisoned by the Nazis,” Gruetters added.

The Associated Press contributed to this report.