Many of the paintings of the French artist Claude Lorrain (1600s) show beautiful, peaceful, imaginary views of a "Golden Age". This picture is set in Ancient Greece.
Golden age is an expression (or term) that people use when they are talking or writing about a time that is past, when everything seemed to be good.
There are several ways that the term can be used.
It can be used for an historic period in a particular place, for example: "The Golden Age of Athens".
This means a time in the history of Ancient Greece when the city of Athens had peace, good government and everyone had enough to eat.
It can be used for a period or style of art or literature, for example: "The Golden Age of Danish Painting".
It can be used in a personal sense, for example: "Harvard was my 'Golden Age'!"
This means that the person speaking says that their time at Harvard University was the happiest in their life.
It could refer to a time in a country when it is undergoing developments and great achievements in science and the arts, the people are happy and lived in harmony and there is a stable economy.