Victory by Susan Cooper - highly recommend
The Diary of Anne Frank
All Quiet on the Western Front (warning, very graphic descriptions of war, may be too intense for a 7th grader)
Biographies would probably be good options for him.
He might enjoy classics. King Arthur stories, Three Musketeers, Robert Louis Stevenson, Mark Twain, etc.
A lot of Newberry winners were historic fiction.
http://www.ala.org/alsc/awardsgrants/bookmedia/newberymedal/newberyhonors/newberymedal
Here's a separate list of historical fiction
https://www.goodreads.com/shelf/show/middle-grade-historical-fiction
He might like time travel series like (these have supernatural themes):
The Dark is Rising by Susan Cooper
Green Knowe by Lucy M. Boston