The decision came after the fifth ballot cast by the 115 cardinals since the papal conclave began Tuesday.
The new pope succeeds Pope Benedict XVI, who became the first pope to resign in hundreds of years. He stepped down February 28, citing advanced age.
The new pope becomes the leader of the world’s 1.2 billion Catholics.
Moments after the newly elected Pope Francis addressed a large Vatican City crowd for the first time since being elected pontiff, a message on the pope’s Twitter account — which had been dormant since Benedict XVI stepped down — said, “Habemus Papam Franciscum.” That translates, from Latin, as, “We have Pope Francis.”