Cardinal Prevost’s choice of the name Leo links him to Leo XIII, a 19th-century champion of social justice, and also recalls Leos I, III and IV, whose diplomatic and military achievements are depicted in Raphael’s “stanze” frescoes, completed for Pope Leo X

The Chicago-born pontiff—the new spiritual leader of 1.3 billion Catholics and the proprietor in trust of the great art and architecture treasures of the Vatican—has publicly supported his predecessor Pope Francis's lead on climate change