Prior to 1991, the ruling African Party for the Independence of Guinea and Cape Verde (Partido Africano de Independência da Guiné e Cabo Verde—PAIGC) was the sole legal party in the Republic of Guinea-Bissau. During the presidency of Luis Cabral, several hundred political opponents of the regime were reportedly murdered and buried in mass graves.
The 1980 coup was condemned by Cape Verdean leaders of the PAIGC, and in January 1981 they broke with the Guinea-Bissau branch to form the African Party for the Independence of Cape Verde. The following November, Guinean party officials decided to retain the name PAIGC for their branch and to expel Cape Verdean founder-members from the party.
Opposition parties were legalized by a new constitution adopted in April 1991. A dozen parties were recognized. Among them were: the Party for Renewal and Development (PRD), which was composed of educated dissidents who quit the PAIGC because of its authoritarianism; the Social Democratic Front (FDS), led by one of the founders of the PAIGC, Raphael Barbosa; the Front for the Struggle for Guinea-Bissau's National Independence, which predates PAIGC and was led by Mindy Kankoila, an early independence leader who had been in exile for 40 years; the National Convention Party (mainly Muslims and FDS dissidents); and the League for the Protection of the Ecology (LPE). The most important opposition party was Bafata, the Guinea-Bissau Resistance-Bafata Movement. Many parties prior to the general elections of 1994 formed a coalition, including the PRD, the FDS, the LPE, the Movement for Unity and Democracy (MUD), and the Democratic Party for Progress (PDP).
Free and fair legislative elections on 3 July 1994 gave the PAIGC a majority of 62 seats. The Guinea-Bissau Resistance (RGB-MB) was second in balloting with 19 seats, 12 for the Social Renovation Party (PRS), 10 for the Front for the Liberation and Independence of Guinea-Bissau, and 6 for the Union for Change Coalition.
In the November 1999 Assembly elections, the Partido da Renovacao Social (PRS), won 38 seats, the Resistencia da Guine-Bissau-Movimento Ba-Fata (RGB-MB) 28 seats, and the PAIGC 24 seats. Five parties garnered the remaining 12 seats in this election, which were part of the second consecutive set of free and fair competitive elections in Guinea-Bissau. Despite Yala's promises to form a government of national unity, the PRS and its ally, RGB-MB dominated the cabinet.