COPENHAGEN—Kim Ryholt of the University of Copenhagen has been collecting and studying Egyptian slave contracts written on papyrus, which are thought to have been looted from a garbage pit in the ancient temple city of Tebtunis. In the 2,200-year-old documents, people signed themselves and their families over as temple servants, even paying a monthly “slave fee.” Ryholt thinks that these slaves may have been people without social status who chose temple slavery over heavier forced labor.