A really good nonfiction to learn about something new?

I am in the mood to get really deep into a subject I may not know much about, and basically I just want to learn! What are some great nonfiction books you've read where you felt you learned a lot? I don't really want it to be a memoir and I don't mind if it is a bit more accademically leaning. In the past I loved Empire of Pain by Patrick Radden Keefe or Doppelganger by Naomi Klein. I am usually more interested in arts, culture, social sciences and history than hard sciences but if the book is really good then I'm open to pretty much anything!