Where did the word memoir come from?

The word "memoir" comes from the Old French word "memoire," which itself comes from the Latin word "memoria," meaning "memory."

The word has been used in English since the 14th century to refer to a record of events or a personal recollection. Over time, the meaning evolved to refer specifically to a non-fiction narrative written from a personal perspective. This typically focuses on a specific period or aspect of the author's life, rather than being a complete autobiography.