As a young poet, Silveira was one of the most prominent critiques of the literary elite in Cape Verde. Silveira was associated with the views of the Claridade group, and argued in favour of an African cultural identity of the islands.
Silveira was a student in Uppsala, Sweden during the 1960s, after having spent a period in China. In Uppsala he had close links with the South Africa Committee of the city, which was crucial for the initiation of solidarity work for the African Party for the Independence of Guinea and Cape Verde (PAIGC) in Sweden. He became the representative of PAIGC in Sweden. Silveira made several visits to Norway, where he established good relations with the Norwegian Council for Africa and the Norwegian Labour Party, and played a role in the securing official Norwegian support to PAIGC in 1972. He also represented PAIGC during visits to Finland.
Silveira was dismissed from his position as PAIGC representative in Sweden in November 1972. According to the PAIGC, his dismissal was a disciplinary action due to Silveira's failure to attend a meeting in Guinea-Conakry. However, the organization expressed its gratitude towards Silveira for his work in establishing links between Sweden and PAIGC. Silveira later worked for the United Nations, representing the U.N. in countries like Somalia, Angola and Mozambique.
With the opening of multi-party politics in Cape Verde after 1990, Silveira was hostile to PAICV (PAICV). In November 1998, he formed his own political party, the Labour and Solidarity Party (PTS). He became mayor of the town of Mindelo.
In 2006 he was elected member of parliament as a PAICV candidate.
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|url=value (help). Cabonet Nederland. Retrieved 2010-02-07.
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