Aleksander Kulisiewicz performing in a Nazi camp prisoner’s uniform, ca. 1960s. Photo: Courtesy of Krzysztof Kulisiewicz Sometimes a word can hit like a hammer, its use smiting our sense of what is decent and humane. In “Sing, Memory,” by Makana Eyre, many readers will learn for the first time that the most abject prisoners in the Nazi concentration camps—so underfed it seemed as though their stomachs and backs would meet—were known as “Muselmänner.” This German word for Muslims, Mr. Eyre suggests, came to be used to “evoke a comparison between the prone state of starving prisoners and a Muslim in...