On the 13th of March 2013 Jorge Mario Bergoglio was elected Pope and thus became head of both the Roman Catholic Church and the Vatican. Which pope name did he choose?

Explanation

The pope is the Bishop of Rome and the leader of the worldwide Catholic Church. In the Catholic Church, the Pope is regarded as the successor of Saint Peter, the Apostle. The pope lives in, and heads up, the Vatican City, a sovereign city-state entirely enclaved within the city of Rome in Italy.