During the Age of Discovery a little-known public servant in the Venetian government, Giovambattista Ramusio, anonymously assembled and edited three volumes – over two million words – that revealed our world as never before. It was, to use a current expression, the biggest Wikileak of the Renaissance. In an enthralling narrative, Andrea di Robilant brings to vivid life the man who used all his political skill, along with the help of conniving diplomats and spies, to ferret out a remarkable collection of journals, private letters and classified government reports, which, when taken together, showed how the world was much larger than anyone previously imagined.