Ranson, along with Bonnard, Vuillard, Serusier, Denis and Roussel, formed a Post-Impressionist group, the Nabis. In 1908 Ranson founded the Academie Ranson where these Nabis painters taught. Ranson was also deeply committed to Theosophy, the philosophy of a para-religious fraternity which draw its articles of faith from all the major religions of the world. Some of his paintings were the outgrowth of his interest in the occult and magic.
Ranson was interested in freeing art from the confines of the easel. He created panel paintings, tapestries, ceramics, book illustrations, sets and costumes for puppet shows and stained glass in addition to his paintings.
