On 15 October 1974, the government of Portugal recognized the Movement for the Liberation of São Tomé and Príncipe (Movimento de Libertação de São Tomé e Príncipe—MLSTP) as the sole legitimate representative for the islands. The party, formed in exile in 1960, at a Pan-African conference in Ghana, originally called itself the Committee for the Liberation of São Tomé and Príncipe (Comité de Libertação de São Tomé e Príncipe—CLSTP). In 1965, CLSTP publicly demanded independence and economic reforms for the islands. At a conference in Guinea in 1972, the CLSTP changed its name to the MLSTP and moved its headquarters to Gabon. Until the declaration of 15 October 1974, the MLSTP remained partially underground and in exile, expressing itself through a legal party, the Pro-Liberation Movement Association, led by the poet Alda de Espírito Santo. After independence, the MLSTP became the only political party. Until 1991, Manuel Pinto da Costa was secretary-general of MLSTP and president of the republic.
With the legalization of opposition party activity, several politicians returned from exile to organize their followers. Miguel Trovoada, an MLSTP founder who had been exiled after challenging da Costa's leadership, formed the Democratic Convergence Party-Group of Reflection (PCD-GR) and, in the 1991 elections, it captured control of the People's Assembly and the presidency. The Democratic Opposition Coalition (CODO) and the Christian Democratic Front (FDC), and other parties together captured 15% of the vote for the legislature.
In December 1992, the MLSTP came back to score a series of landslide victories in municipal and regional elections. It took control of six of the eight regional governing bodies. In the 1994 elections, the MLSTP solidified its control, taking 27 of the 55 seats. The PDC-GR took 14, as did the Independent Democratic Action Party. Only 42% of registered voters turned up. There was a bloodless and short-lived coup amid massive popular unrest due to wage stagnation in 1995. The military leaders held power only briefly before returning the civilian government to power. In 1996, a government of national unity headed by Prime Minister Armindo Vaz d'Almeida was inaugurated.
Nine parties contested the 8 November 1998 parliamentary elections. The MLSTP further solidified it parliamentary grip to 31 seats. The Independent Democratic Action Party (ADI) increased its seats to 14, whereas the PCD-GR) got only 8 seats. São Tomé and Príncipe was one of 15 countries whose politicians formed the Union of African Parties for Democracy and Development (UAPDD) in Namibia in October 1998, aimed at promoting the interests of the continent.
In the July 2001 presidential elections, de Menezes benefited from the support of the Accao Democratica Independente (ADI), the country's largest, but comparatively weak opposition, and five other political forces including the PCD, UNDP, Codo, PRD, and the PPP. Under the country's semi-presidential formula, the dominant parties in the parliament wield considerable powers. Therefore, although this coalition reflected the self-interests of the leaders of these political entities, it assured de Menezes of a constituency sufficient to score 56.3% to 39% of the vote over Pinto da Costa. Three other opposition figures took 5% of the vote.
On 3 March 2002, São Toméans went to the polls to elect a new parliament. The results ended in a deadlock for the MLSTPPSD, which gained 39.6% of the vote, and Force for Change Democratic Movement (MDFM-PCD), which took 39.4% of the ballots. Ue-Kedadji coalition received 16.2%. The number of seats by party was: MLSTP-PSD 24, MDFM-PCD 23, Ue-Kedadji coalition 8.
The Ue-Kedadji coalition comprises the ADI, PRD, Uniao Nacional para Democracia e Progresso (UNDP), Codo, and Partido Popular do Progresso (PPP) and has the support of Miguel Trovoada and his son Patrice. While the MDFM-PCD actually received more votes than the MLSTP-PSD, the latter won the proportional vote at the district level.