Like many left-wing intellectuals in 1930s and 1940s France, Césaire looked toward the Soviet Union as a source of progress, virtue, and human rights. He later grew disillusioned with the Soviet Union after the 1956 suppression of the Hungarian revolution. He announced his resignation from the PCF in a text entitled "Lettre à Maurice Thorez" (Letter to Maurice Thorez). In 1958 Césaire founded the Parti Progressiste Martiniquais. With the Parti Progressiste Martiniquais, he dominated the island’s political scene for the last half of the century. Césaire declined to renew his mandate as deputy in the National Assembly in 1993, after a 47-year continuous term.