Conversation so far:
What is Gustave Courbet's Realist manifesto?
Gustave Courbet wrote a Realist manifesto for the introduction to the catalogue of this independent, personal exhibition, echoing the tone of the period's political manifestos.
What was included in the Realist Manifesto by Gustave Courbet?
Gustave Courbet's goal as an artist to translate the customs, the ideas, the appearance of my epoch according to my own estimation.

Question: What happened to the Manifesto?
Self-contained rewrite: What happened to the Realist Manifesto by Gustave Courbet?