Diethard Leopold, a Viennese psychotherapist whose father founded the Leopold Museum, is aiming to settle all outstanding Nazi-era claims for art in its collection within a year. Leopold, 54, was appointed to the board of the museum’s foundation by his father in June, days before Rudolf Leopold’s death. In July, the museum agreed to pay $19 million to the heirs of the Jewish art dealer Lea Bondi Jaray to settle a decades-long dispute over Egon Schiele’s portrait of his lover Wally, stolen by the Nazis in the 1930s. The Leopold Museum owns 44 Schiele paintings and 180 works on paper, the biggest collection of the artist worldwide.