Following the ground-breaking work by Courbet and others, it was for the impressionists to take the next step forwards in the development of art and painting in France.
It is not easy to understand now, but at the time the impressionists received an enormous amount of criticism from the established art world because of their approach to painting - broad brush strokes, dabs of colour, detail often not clearly painted - it was seen as childish and amateurish.
Many in the art world at that time saw impressionism as an unsophisticated, casual approach to painting to be mocked and rejected, and the impressionists were frequently forced to hold their own exhibitions, being prevented access to the formal exhibitions of the time.
The impressionist 'rebellion' against the established art world was perhaps always inevitable. The existing 'Academy of Arts' world was limited in what it could offer, and was, essentially, only painting a small part of the world and that in a very artificial manner.
It must always have been only a matter of time before artists realised that they weren't capturing the world around them in any meaningful shape or form. The impressionists spent much time discussing the function of their painting and art, and what it should be like.
The painters rejected public opinion, or more specifically the opinion of the art world and art critics at that time. They also rejected the constraints of a painting studio - preferring to paint in the location which they were trying to recreate. They believed that any scene was appropriate for painting, even a 'dull' subject such as a sunrise or a boat bobbing on the water, and didn't want to be told what they should paint.
We now recognise that this approach more accurately depicts the way we really see the world - when we look at a lily pond we don't immediately see every detail of every petal, rather we have a general impression of the flowers, the light hitting the water, the shade of a nearby tree. We also see a pretty scene, well worth recording on canvas, despite the absence of a great monument or personnage.
Most of the important Impressionists were either French, or foreign born but resident in France. See articles about some of the most influential impressionist painters:
Few could have guessed at the time how important this development really was, or how quickly the world would forget much of the classical painting that had come before.