As a cul­tur­al his­to­ri­an, and the son of a Ger­man Jew­ish refugee father, I was drawn in imme­di­ate­ly to the resur­gence of inter­est in the fate of Nazi stolen art, which began in the late-1990s. Even so, I was con­cerned that dwelling on the dark­ly enthralling sto­ry of how Nazis and col­lab­o­ra­tors ran­sacked Jew­ish-owned art col­lec­tions obscured larg­er his­tor­i­cal ques­tions: How did cer­tain Jews acquire so much great, old and mod­ern art in the first place? How, against all odds, did these out­siders come to play a piv­otal role in shap­ing the mod­ern art world? How did they become the old mas­ters’, new mas­ters, and the mod­ernists cham­pi­ons? And how, final­ly, did their sud­den promi­nence in a realm pre­vi­ous­ly dom­i­nat­ed by non-Jews fuel a furi­ous back­lash from anti­semites and, then, a vio­lent onslaught from Nazis.

This is the untold sto­ry of Nazi stolen art that I set out to tell in Belong­ing and Betray­al, by focus­ing on the rise and fall of a small cir­cle of remark­able indi­vid­u­als and fam­i­lies of Jew­ish ori­gin. What caught, and kept, my imag­i­na­tion, were the fas­ci­nat­ing sto­ries sur­round­ing the pro­tag­o­nists’ lives and works.

My feel­ings and thoughts about the pro­tag­o­nists changed over time. I tried as best I could to sym­pa­thize with their sit­u­a­tions, if not always their actions; I could not help but respect and admire the remark­able accom­plish­ments of these men and women— many of whom came from very mod­est back­grounds and had lit­tle in the way of for­mal edu­ca­tion— who devel­oped aston­ish­ing eyes by scru­ti­niz­ing count­less works of art in muse­ums, gal­leries, and exhibits.

I offer three char­ac­ter sketch­es: a col­lec­tor, a deal­er, and an artist.

As a child grow­ing up in New York City, I knew B. Alt­man as one of the metropolis’s lead­ing depart­ment stores. I recall going there at least once with my moth­er when she was shop­ping for a spring coat. It was only many years lat­er that I came to appre­ci­ate the impor­tance of the extra­or­di­nary art col­lec­tion that its founder, Ben­jamin Alt­man, had put togeth­er. The son of Bavar­i­an Jew­ish immi­grants, Alt­man took over his father’s very mod­est dry goods busi­ness and turned it into a great empo­ri­um. Alt­man chose the goods he car­ried with much the same care and scrupu­lous­ness that he lat­er put into select­ing art objects. Alt­man was an enlight­ened employ­er, who cared deeply for the wel­fare of the peo­ple who worked for him. Alt­man was not a show-off. What he lacked in bravu­ra, he more than made up for with an unerr­ing eye for qual­i­ty, and an excep­tion­al gift for orga­ni­za­tion; both qual­i­ties were of great use as he built his art col­lec­tion, housed in the pri­vate muse­um in his Fifth Avenue man­sion. Pru­dent and delib­er­ate, Alt­man pon­dered pos­si­ble acqui­si­tions and did not take well to being rushed or pushed. This frus­trat­ed his prin­ci­pal deal­ers, Hen­ry and Joseph Duveen, who could not resist urg­ing one pic­ture after anoth­er on him.

Start­ing out with pot­tery, Alt­man worked his way toward the Old Mas­ters, includ­ing the great Ital­ian, Span­ish, and Dutch painters of late the medieval and ear­ly mod­ern era. And, though he was par­tic­u­lar­ly drawn to Rem­brandt, as were many non-Jew­ish New York mer­chants, he want­ed to build an ency­clo­pe­dic col­lec­tion, which rep­re­sent­ed dif­fer­ent schools and eras. He did just that on the Duveens’ advice. What Alt­man lacked in for­mal edu­ca­tion he more than made up for in intel­li­gence, effort, and curiosity.

Unlike many art col­lec­tors then and now, though, Alt­man was unin­ter­est­ed in buy­ing art to win social sta­tus. A life-long bach­e­lor, Alt­man belonged to ​“Our Crowd,” the cir­cle of well-to-do Ger­man Jew­ish fam­i­lies in New York. He rarely showed his art and he kept his dis­tance from the bur­geon­ing Met­ro­pol­i­tan Muse­um of Art, a pre­serve in which Jews were unwel­come. Toward the end of his life, Alt­man had to decide what to do with his mag­nif­i­cent art col­lec­tion. Would he donate it to the Met­ro­pol­i­tan, build a pri­vate muse­um, or bequeath it to his fam­i­ly members?

Léonce Rosen­berg, born and bred in Paris, cham­pi­oned the mod­ern, unlike Alt­man, who favored Old Mas­ters. In looks, tem­pera­ment, and approach, Léonce and his younger broth­er Paul, were marked­ly dif­fer­ent. Both were true art lovers, but Paul was by far the more com­mer­cial, can­ny, and cau­tious. On the oth­er hand, Léonce was ide­al­is­tic, impul­sive, and vision­ary, a con­fi­dent risk-tak­er in his taste and stead­fast in his com­mit­ments. For a time, the broth­ers ran the fam­i­ly gallery that their father Alexan­dre had built. But they could not— or would not— get along. When they part­ed ways, Paul stayed put in the gallery while Léonce went out on his own.

What would he do next? He drift­ed for a time and then delved into col­lect­ing antiq­ui­ties. One day he came across a small gallery run by a Ger­man Jew­ish émi­gré, Daniel-Hen­ry Kah­n­weil­er. He could not wait to start col­lect­ing the Cubist pic­tures dis­played there, and began doing so at a time that more con­ven­tion­al con­nois­seurs regard­ed them as inde­ci­pher­able, not to men­tion unsellable.

A man in search of a mis­sion, Léonce thought he had found his cause dur­ing World War One. While in uni­form, he sup­port­ed Picas­so and the Cubists after their reg­u­lar deal­er, Kah­n­weil­er, reluc­tant­ly took refuge in Switzer­land. With the end of the war in sight, Léonce opened a gallery ded­i­cat­ed to an idea, the Effort Mod­erne. On Sun­days, he host­ed gath­er­ings of estab­lished and aspir­ing artists and writ­ers. Addi­tion­al­ly, he pub­lished a house jour­nal ded­i­cat­ed to avant-garde art.

Léonce Rosenberg’s pro­found com­mit­ment to the art he cham­pi­oned was nev­er in ques­tion, how­ev­er, the finan­cial via­bil­i­ty of his gallery was . Despite his com­mer­cial and finan­cial posi­tion, Léonce was deter­mined to keep his gallery going at all costs. Although he had grown up in the shad­ow of the Drey­fus Affair, noth­ing had pre­pared Léonce (or oth­er French Jews) for the dis­as­trous fall of France in mid-June 1940 and the ensu­ing Ger­man Occu­pa­tion. Could he keep his dig­ni­ty and, above all, his fam­i­ly safe in the face of unremit­ting humil­i­a­tions, threats, and dangers?

Artists abound in Belong­ing and Betray­al, among them Mon­et, Pis­sar­ro, Degas, Renoir, Lieber­mann, Van Gogh, Vuil­lard, Picas­so, Braque, Matisse, Klimt, Kokosch­ka, and Schiele. One of the most intrigu­ing and least known fig­ures is Abra­ham Mint­chine. Russ­ian-born, he was one of a band of Jew­ish émi­gré artists who came to Paris in the ear­ly decades of the twen­ti­eth cen­tu­ry in search of artis­tic edu­ca­tion and glo­ry. He was for­ev­er chas­ing his fel­low Russ­ian émi­gré and near con­tem­po­rary, Chaim Sou­tine, whose work haunt­ed him . René Gim­pel, expert deal­er in Old Mas­ters and chron­i­cler of the inter­war art world, was so con­vinced of Mintchine’s genius that he took him under his wing. It would be dif­fi­cult to exag­ger­ate the depth of Mintchine’s desire to take in what he saw at the Lou­vre with Gim­pel. Despite occa­sion­al set­backs, Mint­chine con­tin­ued to make progress as a painter of por­traits and cityscapes. As he strug­gled with ill health and ten­u­ous finances, he endeav­ored to sup­port his wife and young daugh­ter. All the while, one ques­tion remained: would he ful­fill the promise that Gim­pel saw in him?

One of the most inspir­ing and mov­ing pho­tographs that I came upon pic­tured a young, attrac­tive, and smil­ing Abra­ham Mint­chine cross­ing a bridge in Paris with his arms wide open in expec­ta­tion of things to come. For Mint­chine, as for so many oth­er Jews in the art world — deal­ers, col­lec­tors, crit­ics, his­to­ri­ans, and artists — art was a bridge in more ways than one. It sym­bol­ized the prospect of bridg­ing the gap between Jew and non-Jew by find­ing com­mon ground in cul­ture. The bridge sym­bol­ized the pro­found desire for accep­tance and suc­cess that ani­mat­ed so many Jews. Even so, nei­ther Abra­ham Mint­chine nor oth­er aspir­ing Jews knew that what await­ed them on the oth­er side of the bridge was betray­al rather than belonging.