In the late 1930s, Graham Greene was commissioned to visit Mexico and find out how the inhabitants had reacted to the brutal anti-clerical purges of President Calles. His journey took him through the tropical states of Chiapas and Tabasco, where all the churches had been destroyed or closed and the priests driven out or shot; and it provided him with the setting and themes for his novel "The Power and the Glory". This book describes his travel experiences in Mexico.