Fortier’s theatre/theory
Theory/Theatre: An Introduction - 2nd Edition https://www.amazon.com/dp/041525437X/ref=cm_sw_r_cp_api_i_OGjiFb43WSE5J
But really, this book is fab for both history AND theory:
Theatre Histories: An Introduction https://www.amazon.com/dp/041546224X/ref=cm_sw_r_cp_api_i_zFjiFbNFAMNCK
I use Wilson and Goldfarb Living Theatre in my theatre history classrooms. And I find Brockett to be dreadful (good history, BORING writing)