Suite Française by Irène Némirovsky (2004, published posthumously) — Némirovsky was a Ukrainian-born Jewish novelist living in France who was deported and killed at Auschwitz in 1942. Her unfinished novel, written during the occupation and hidden by her daughter for decades, depicts French life under the German occupation and the moral compromises it produced. It is the essential literary companion to the Vichy period, written from inside it.
Vichy: An Ever-Present Past by Henry Rousso (1994) — Rousso's influential work examines how France has remembered and misremembered the Vichy period since the Liberation: the myths, the amnesia, the slow and painful reckoning that began in the 1970s. Essential reading for anyone who wants to understand why the city's commemorative approach has been so contested.
A Moveable Feast by Ernest Hemingway (1964) — Not about Vichy specifically, but the France of the 1920s that Hemingway describes is the France that made Vichy's resort culture possible: the same confidence, the same pleasure in food and wine and landscape, the same sense that France was the civilised centre of the world. Reading it before visiting gives the spa town's elegance a specific historical moment.
The Collaboration: Hollywood's Pact with Hitler by Ben Urwand (2013) — A sideways approach: the book examines American complicity with Nazi Germany before the war, and by extension the broader tendency of powerful institutions to accommodate rather than resist. Vichy is the French version of this accommodation, and reading about it from an unexpected angle illuminates the regime's wider context.