It is tantalizing to learn that the military team was initially told that a seventh-century Babylonian Talmud was in the cache; it was never found, but important items were looted.

The salvation of the rest was as unpredictable as its presence in that basement. The extraordinary efforts required (supported by Donald H. Rumsfeld, then defense secretary) may have salved the consciences of those in the United States administration who failed to stop the torching of the great Central Library in Baghdad a few weeks earlier.

As for the Jewish population’s decline, perhaps the collection will eventually shed light on the massacres, hangings, expulsions and degradations that befell its members beginning in the 1930s. But the exhibition’s text provides a broad portrait. Nazis and their Islamic allies began making inroads, culminating in the Farhud pogrom in 1941; the exhibition says 180 Jews were killed and hundreds more injured; other estimates are higher. Later that decade, Iraq’s entry in the war against Israel led to edicts removing Jews from public life and imposing restrictions on their commerce and travel. Mass migrations followed, requiring forfeiture of property.

Some sense of the delicate maneuvering required by the remaining Jews in Iraqi is clear here in a 1949 Hebrew primer. Two pages with a poem declaring loyalty to King Faisal II were ripped out after he was killed in a military coup in July 1958. It is as if mixed feelings of loyalty and vulnerability first required including the pledge and then required destroying it.

Difficulties mounted again with the 1963 rise of the Baath Party. And Islamist attacks in recent years have not inspired confidence about returning this collection. What evidence is there that Iraq will now treasure artifacts of Jews and other cultures? How would this archive be freely studied? Since these documents were forcefully taken from the Jews of Iraq, was the 2003 State Department agreement even valid? But if they belonged to that population, who are its rightful heirs? Iraqi Jews now living in other countries?

The one thing that is clear is that this textual trace of a community’s life is not a backwater chronicle. The exhibition reminds us that while the West’s influence on Judaism has been profound, it is by the waters of Babylon that many texts and practices of exilic Judaism were codified, beginning a long evolutionary journey — even if this strand came to a grievous end in the muck of Iraq’s Mukhabarat.