As the leader of Vatican City, he is the head of a sovereign nation. But maintaining dual citizenship as a foreign head of state can “raise complex questions of international law,” according to the State Department.

A papal conclave is set to begin in Vatican City starting May 7, during which cardinals from around the world will elect the next leader of the Roman Catholic church. The tradition occurs any time a pope dies or resigns from the office. Pope Francis died April 21, the day after Easter.

White smoke billowed over the Vatican on Thursday to signal a cardinal has been elected as the 267th leader of the Catholic Church. Why it matters: The newly elected pope, who has not yet been publicly named,