 The Spanish Socialist Workers' Party and the "Esquerra Republicana de Catalunya" (ERC) were banned in 1939, while the Communist Party of Spain (PCE) went underground.The Basque Nationalist Party (PNV) went into exile, and in 1959 the ETA armed group was created to wage a low-intensity war against Franco.Franco's Spanish nationalism promoted a unitary national identity by repressing Spain's cultural diversity.