It was Alfred Wiener’s new employers who apparently first referred to his enterprise as “the Library.” After the war, the library found new patrons among wealthy Jews in Britain and the United States. It also played a role in assisting in the prosecution of Nazi war criminals at Nuremberg. Yet even though its twin focus on documenting the devastation of Jewish communities of Europe and the ideology that led to that destruction was unrivaled — the Israeli memorial at Yad Vashem was not built until 1953 — the Wiener Library struggled to survive. Its widely publicized involvement in the prosecution of Adolf Eichmann brought only a temporary respite in a long period of decline.

For years, a steadily shrinking staff struggled to maintain the aging collection and to catalog the growing archive of Holocaust-related clippings culled by a group of volunteers, some of whom had themselves survived German death camps.

In his biography of Mr. Wiener, who died in 1964, Ben Barkow blames a combination of the founder’s personal failings, academic politics and the vagaries of ethnic institutions for the library’s decline. But Mr. Barkow, the library’s current director, believes that his institution is on the verge of a renaissance. “Although we don’t have any formal relationship with any university, we are very keen to be part of the life of our academic neighbors,” he said in an interview.

Dan Plesch, the author of “America, Hitler and the UN,” said of the library, “It’s an astonishing resource.” In researching his book, Mr. Plesch, who teaches at the School of Oriental and African Studies, came across a statement issued Dec 17, 1942, by the British, American and Soviet governments that seemed to suggest fairly detailed early knowledge of the Holocaust, warning that the German authorities “are now carrying into effect Hitler’s oft repeated intention to exterminate the Jewish people in Europe.”

“The Wiener Library were able not just to authenticate the document but to place it into context,” Mr. Plesch said.

Increasing the likelihood of such collaborations was a major factor in moving the library to Bloomsbury, said Joanna Bourke, a Birkbeck history professor involved in the negotiations. “It’s one of the great underutilized resources,” she said. “People tend to categorize it as being just about the Holocaust, or about European Jews. But I’ve used it in my work on women’s organizations. And for anyone interested in health care or the history of medicine in Britain, they have a wealth of material.”

Referring to the library, Ms. Bourke added: “They wanted to retain their independence, which they have. But by moving them effectively onto campus, they’ll get a lot more visitors, and a lot more researchers will be able to use the collection.”