Jung argued that the collective unconscious manifested itself in

He argued  that the collective unconscious manifested itself in fairytales.
For example, we could analyze the typical western fairytales where knights had to fight a really strong monster in order to get the princess.
This story is manifested from the fact that male has to pass several life obstacles (career, fitness, competition with other males, etc) in order to get a mate.

fairytales
 A fairy tale is a type of short story that typically features folkloric fantasy characters, such as dwarfs, dragons, elves, fairies, giants, gnomes, goblins, griffins, mermaids, talking animals, trolls, unicorns, or witches, and usually magic or enchantments.