John Calvin (July 10, 1509- June 27, 1564) was a French Protestant theologian during the Protestant Reformation and was a central developer of the system of Christian theology called Calvinism or Reformed theology. He is renowned for his teachings and writings, in particular for his Institutes of the Christian Religion.

For more information:

http://www.calvin.edu/about/about_jc.htm

http://en.wikipedia.org/wiki/John_Calvin