The National Liberation Front, which emerged in 1967 as the strongest faction in the disputes before South Yemen's independence, became the United Political Organization– National Front in 1970 and changed its name to the Yemeni Socialist Party (YSP) in 1978, when two smaller leftist parties were merged with it. This Marxist-Leninist organization, the PDRY's lone political party, was the only group to offer candidates in the 1986 legislative elections and survived to represent southern interests in the unified Yemen.
In pre-unification north Yemen, political parties in the Western sense played no role. Tribal allegiances were more important political factors. After unity, the northern leader, General Saleh, formed the General People's Congress (GPC), which became the country's largest party. The second-largest bloc in the parliament is held by the Islaah Party (The Yemeni Congregation for Reform), a fusion of tribal and Islamic interests that opposed the unity constitution because it did not sufficiently adhere to Islamic principles. At least forty smaller parties have been active in the politics of unified Yemen, but the GPC, Islaah, and the YSP are the only ones of national significance. After the 1994 civil war, the GPC and Islaah formed a coalition government to establish civil order.
In the April 1997 legislative election the GPC won a landslide victory and no longer governed in coalition with Islaah. The YSP boycotted the April 1997 legislative election. In addition to these three main parties, as of 1997, the other parties active in the political arena that had fulfilled Yemen's legal procedures to practice political activities were the Peoples Nasserite Reformation Party, Liberation Front Party, Nasserite Democratic Party, League of the Sons of Yemen, Federation of Popular Forces, National Arab Socialist Baath Party, National Democratic Front, Al Haq Party, Yemen League Party, and the National Social Party. As of 2003, the active parties are GPC, Islaah, Yemeni Socialist Party (YSP), Nasserite Unionist Party, and the Arab Socialist Rebirth Party.
In September 1999 Yemen held the first direct presidential elections ever held on the Arabian peninsula. Longtime president Saleh captured 96.3% of the vote; Najeeb Qahtan al-Shaabi, his only opponent, won 3.7% of the vote. Led by the YSP, a coalition of opposition groups boycotted this election.