The novel is based on Levinson's archives, dug out of the ruins of the Ghetto after the war. The archives are fictional but the information contained in them is based on authentic records. Hersey had translators read those records into a recorder. There were diaries, medical records, letters, and songs which became part of the material for his novel.

Hersey began looking for these materials early in 1947 and lived with his tapes for almost a year and a half before starting to write.

When about four-fifths of the way through his first draft, Hersey decided that his whole plan was wrong. He had been writing a third-person singular narrative with occasional interchapters by Noach Levinson commenting on what was taking place. But Levinson was too important to the narrative to be confined to this system. Hersey decided to rewrite the whole book, using Levinson's voice throughout. The second...