What role did cultural diffusion play in the development of common themes in the world's literature? When new schools were set up in neighboring countries, children were taught the stories of both countries.
When people traveled or moved to other parts of the world, they took their stories shared them, often adapting them.
When different parts of the world developed systems of writing, they borrowed the literature of other cultures.
When the printing press was invented, its inventors went looking for stories to publish from around the world.