Excerpts from Books and Wikipedia
"The French philosopher Jean-Paul Sartre (1905-1980) believed that in the wake of the unparalleled destruction of World War II, the absurdity of life was the most basic discovery one could make. Denying the existence of God, existentialists like Sartre posited that life has no meaning. Their conclusion was that a person could only truly find any fulfillment while living "a suspended death" by becoming aware of his or her freedom to choose and to act. Sartre titled one of his novels Huis clos (No Exit), as he believed there was nothing beyond this life. Sartre's novels glorify the individual spirit seeking freedom, not through Enlightenment rationalism, but rather through the very comprehension of life's irrationality. However, more than this, Sartre believed that violent revolution could free the individual from the human condition by allowing him or her to find truth by redefining reality. To this end, he joined the French Communist Party when the war was over. However, existentialism slowly lost its grip on French intellectual life, at least partially because of growing disillusionment with the Soviet Union among many leftist intellectuals." [Merriman: Modern Europe, p. 1301]