Elie Nadelman is widely recognized for his spare modernist sculpture, but an exhibition at the New-York Historical Society reveals that he was also a trailblazing collector of folk art. Together with his wife, Viola Spiess Flannery, Nadelman assembled the first significant collection of American and European folk art, which eventually comprised some fifteen thousand objects. The dashing couple’s collecting enterprise began soon after their marriage in 1919 and gathered steam during the heady decade of the 1920s.