I recently finished reading History of Beauty by Umberto Eco. While the book doesn't cover everything (perhaps with the subject of beauty it is impossible to have a complete history), it does describe several aspects of beauty and historical cultural ideals. The book also features many nice color reproductions of various artworks. While the overarching statement seems to be the familiar truism that beauty is in the eye of the beholder, and that the notion of ideal beauty is subject to many influences, beauty remains as indefinable and illusive as ever (which is a good thing for artists who enjoy the pursuit). The book does explore interesting ideas though, such as "beauty cannot exist without its opposite." This idea that ugliness makes beauty apparent is analogous to other opposites, such as darkness defining light with examples in the paintings of Georges de La Tour that feature extremely dark scenes lit by candlelight, or the use of chiaroscuro in the paintings of Caravaggio, where the form-defining light often takes on religious meaning in contrast to its surrounding darkness. Beauty may exist without ugliness, but perhaps our perception of it is sharpened when its opposite is present, as with good and evil, or hope and despair. The book also discusses the alignment of beauty with virtue, and how dubious aesthetic beauty can be. Overall, the book offers a nice collection of thoughts to ponder further.
Mary Magdalene by Georges de La Tour (above)