Viriato da Cruz and others formed the Movement of Young Intellectuals, an organization that promoted Angolan culture, in 1948. Nationalists sent a letter to the United Nations calling for Angola to be given protectorate status under UN supervision. In 1953 Angolan nationalists founded the Party of the United Struggle for Africans in Angola (PLUA), the first political party to advocate Angolan independence from Portugal. Two years later Mário Pinto de Andrade and his brother Joaquim formed the Angolan Communist Party (PCA). In December 1956 PLUA merged with the PCA to form the Popular Movement for the Liberation of Angola (MPLA). The MPLA, led by da Cruz, Mário Andrade, Ilidio Machado, and Lúcio Lara, derived support from the Ambundu and in Luanda.