One morning after a sauna, German author Jochen Hellbeck was wandering the streets of perestroika-era Moscow, and saw an unusual sign above a door that read: “People’s Archive.” Curious, he went inside, but was confused to find himself in a music shop. Speakers blared Russian pop. Shelves were lined with old transistor radios and cassette tapes. Asking about the sign, he was directed to a backroom. “Like most archives, it was dark and cool,” he recalls in his 2006 book Revolution on my Mind. Metal shelves lined the walls. Tiny barred windows let in almost no light. A young assistant showed him around and explained that the intention of the archive was to collect and preserve the voices of ordinary people, to challenge the manufactured history of the Soviet state.

The archive was full of journals, diaries and personal notebooks. Hellbeck found himself entranced by the diary of a ...