1450s: German businessman Johann Gutenberg prints the first Bible (in Latin) from a printing press.

1510s: Martin Luther's theses and other literature promoting reformation of the Catholic Church are quickly disseminated through printing presses.

Today: There continues to be a market for printed books, though literature is also being spread and published by electronic media.

1450s: After decades of bitter rivalry, the Italian city-states form the "Italian League" and agree to protect each other from outside attacks.

1510s: Machiavelli writes The Prince, an instruction manual on how monarchs gain and wield power. He addresses it to the Medici family, the unofficial rulers of the Florentine republic.

Today: After many transformations in Italian government, city-states have been abandoned in favor of a democratic republic.

1450s: After fifty years, Italian sculptor Lorenzo Ghiberti completes his famous bronze doors for the northern and eastern portals of the...