Welcome, Nabi. I’m not sure what ancient civilizations you plan to study, but one of my favorite authors for art study with children is Shirley Glubok. She has books about:
Art of Ancient Egypt
Ancient Indians of the Southwest (and other books about other Native American nations such as the Eskimo, Woodland Indians)
Art of Africa
Art of Ancient Greece
Art and Archeology
Art of Ancient Mexico
Art of Ancient Peru
Art of Ancient Rome
Art of India
Art of the Vikings (I love this book!)
Olympic Games in Ancient Greece
I haven’t read all of these books, but I thoroughly enjoyed the books of hers that I have read. (She has many books about American Art, by the way).
The layout of her books make them particularly useful for a CM style of study. It’s easy to read one page-spread with narration per sitting. The layouts in the books are very well-done, the images are large, the text explains the images in just the right amout of detail and provides context for the art, which I especially appreciate.