Update: Agatha Christie *Was* a Skilled Historian!
My curiosity piqued by my own remarks of a couple of days ago, I looked up Christie's Wikipedia bio, and discovered that she was, in fact an accomplished archaeologist (which as R.G. Collingwood, himself a renowned archaeologist , noted, is merely history done with artifacts instead of documents). Her husband, a professional archaeologist, once told here that she knew "more about prehistoric pottery than any woman in England." So my guess proves correct.