7. Pope Benedict XVI (Pier Paolo Cito/AP Photo)

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Title: Pope, Roman Catholic Church
Age: 84

The spiritual leader to one-sixth of the world's population — 1.2 billion souls — delivers the final word on matters of abortion, gay marriage, female priests and, most recently, Occupy Wall Street. In October the Vatican called for a supranational authority to oversee the global economy: "To function correctly the economy needs ethics, and not just of any kind but one that is people-centred."

2011 lowlight: Two victim groups asked the International Criminal Court to investigate and prosecute Pope Benedict XVI for covering up instances of sexual abuse.

* Video: The Pope's first-ever tweet

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