Ludwig Lewisohn is nearly forgotten today, but in his day he was a literary celebrity. He was so well-known, in fact, that his marital scandals—multiple divorces, an accusation of bigamy, flight to Europe with a decades-younger woman, a second wedding interrupted by a hysterical jilted lover—made national headlines. Through it all, he kept writing, publishing 35 books by the time of his death in 1955. A passionate champion of   sexual freedom, Lewisohn was equally zealous to promote Zionism and "Jewish self-realization." The novel The Island Within (1928), based on his own Jewish reawakening, was a polemical summons to American Jews to return to their "native tradition."

Born in Germany in 1882, Lewisohn was raised as a Methodist in Charleston, South Carolina. After being informed by his graduate adviser at Columbia "how terribly hard it is for a man of Jewish birth to get a good position," he abandoned his dream of becoming an English professor and instead became a critic, novelist, and autobiographer. A journey to Palestine in 1925, taken on the advice of Chaim Weizmann, caused him to embark upon "the great study" of Jewish civilization of which The Island Within was among the first fruits.

Chronicling four generations of a Jewish family named the Levys, the novel begins in Vilna in 1840 with Mendel, a Hebrew-school teacher who harbors a "dark secret." Longing for the forbidden knowledge of nature and geometry, Mendel is "dry of heart," with neither glow nor fervor to his prayers. For the money, he accepts the job of traveling agent for a rich and secularized brandy distiller, but, left with no time for reading or study, he grows nostalgic for "his little school, for the icy evenings in the library of the synagogue, for the warmer contacts and argumentative exercises of the beth hamidrash." Worse yet, his son Ephraim leaves the yeshivah, shaves off his earlocks, adopts the latest German fashions, and marries the distiller's daughter. The son sees no reason to regret his actions. "Were not new Jewish voices coming out of the West?" he asks. "Could not one be a European and a Jew?"

The pattern is thus set by which the Levys slough off the Jewish religion, a process taking up the first half of The Island Within. Ephraim's son Jacob emigrates to the U.S. and establishes a thriving furniture business, becoming more German than American; even in America, German culture signifies the romance of modernity. But it is Jacob's son Arthur—Mendel's great-grandson—who is the family's first thoroughly American and thoroughly modern man, his very name measuring how far the Levys have progressed in abandoning their "ancestral consciousness."

The second half of the novel is devoted to Arthur's story. A cool and aloof rationalist, he trains to become a Freudian psychiatrist, remaining true to the highest principles of science and morality by quitting the staff of a hospital for the insane over the abuse of patients ("God-damn-interfering-kikes," a colleague seethes). Soon, having opened a private practice in New York, he meets and marries Elizabeth Knight, a beautiful young writer who is the daughter of a Christian reformist preacher. They have a son, but their relationship remains distant, polite, without passion.

After several years, Arthur thinks he knows why: he and Elizabeth are of different "kinds." While she lives in a "stream of tradition that is native to [her]," he has nothing of the sort. Instead, he has been uprooted from Jewish tradition—and not only he, but an entire population that had sought the "protective mimicry" of blending in with its Christian neighbors. "Jews like himself," he reflects, "who denied any tradition or character of their own, were really trying to do a thing that was unhuman, that no one else was trying to do." 

And so Arthur "goes back to the Jews," although it is not clear just what this going-back involves. Separating from Elizabeth, he signs on with a fact-finding commission to Rumania "to investigate the condition of the Jewish communities there." But after that? Will he undertake to master a Jewish language? Study the Talmud? Emigrate to Palestine? His plans are unclear. Aside from the simple act of identification, his return to the Jews is entirely negative, a rejection of his long effort to assimilate into the Christian majority. "I didn't have to resur­rect the Jew," Arthur tells his wife. "I just put away a pretense—a stubborn, hard, protective pretense."

His brother-in-law Eli makes a far more assertive choice. After briefly leaving his wife and daughter, he asks to be taken back, but only if Hazel agrees to "move to a Jewish neighborhood," "have some more children," bring them up as "observant Jews . . . no matter what they believe," and "be a Jewish wife same as her mother or mine." If so, he will never again give her cause for complaint.  Rising to the occasion, Hazel herself suggests that they "join a nice congregation."

Lewisohn could not imagine making such a choice for himself. At the end of the novel, Arthur is prepared for anything—and nothing.

Several decades later, a cohort of young American Jews, arriving at a similar crossroads in the wake of the Six-Day War, and buoyed in part by a nationwide search for "roots," would discover that their happiness, too, depended upon returning to their ethnic origins. Most had never heard of Lewisohn, although a reading of The Island Within might have led them to an overwhelming question: "Why not, since one was a Jew and had to live Jewishly, get . . . the maximum good out of one's Jewishness, one's racial poetry, one's ancestral history?" Lewisohn's challenge remains, even if the answer must be sought elsewhere.

D.G. Myers is a critic and literary historian at Texas A&M University and the author of A Commonplace Blog. This is the fifth in a series by him on landmarks in American Jewish literature.