The encyclical of Pope Pius XI, dated May 13, 1931, published on the fortieth anniversary of Pope Leo XIII's Rerum Novarum. Its theme is a strong condemnation of the control of international finance and credit by a small number of financiers who thus supply "so to speak, the life blood to the entire economic body . . . so that no one can breathe against their will." As a result the State "has become a slave, bound over to the service of human passion and greed."