Richard F. Gombrich 
Theravada Buddhism [PDF ebook] 
A Social History from Ancient Benares to Modern Colombo

Written by the leading authority on Theravada Buddhism, this up-dated edition takes into account recent research to include the controversies over the date of the Buddha and current social and political developments in Sri Lanka. Gombrich explores the legacy of the Buddha’s predecessors and the social and religious contexts against which Buddhism has developed and changed throughout history, demonstrating above all, how it has always influenced and been influenced by its social surroundings in a way which continues to this day.