created by the idea of

Solution 1:

The project was first conceptualized by John Doe.

Conceptualize Form a concept or idea of (something)

Also for a more 'project' orientated definition:

Conceptualization:

The ability to invent or formulate an idea or concept. The conceptualization phase of a project occurs in the initial design activity when the scope of the project is drafted and a list of the desired design features and requirements is created.

Solution 2:

This project was inspired by John Doe.

oxfordlearnersdictionaries.com:

inspire verb
2. [usually passive] inspire something
to give somebody the idea for something, especially something artistic or that shows imagination

His paintings were clearly inspired by Monet’s work.

Solution 3:

We could say

This project was John Doe's brainchild.

This means the idea came from his brain, that is to say, he thought of it.

Here is a link to brainchild in the Oxford dictionary.