The SDF was launched in
Bamenda on May 26, 1990 in opposition to the ruling
Cameroon People's Democratic Movement; following the launching rally, six people were killed by security forces. The party held its Constitutive Assembly on February 3, 1991 and elected its National Executive Committee. The party refused to sign the Tripartite Declaration of November 1991, and it chose to boycott the
March 1992 parliamentary election, along with the
Democratic Union of Cameroon, due to the government's failure to meet opposition demands, which included the establishment of an independent electoral commission to oversee the election. However, the party announced at its May 1992 national convention that it would take part in the presidential election later that year. Fru Ndi, the SDF candidate in the
October 1992 presidential election, received about 36% of the vote against about 40% for incumbent President
Paul Biya, according to official results. The SDF believes he was denied victory "at gunpoint". He has now been largely criticized in the national press for moving residence to
Yaoundé. The SDF won 43 seats in the
National Assembly in the
May 1997 parliamentary election, receiving its best results in
Northwest Province, where it won 19 out of 20 seats; it also won a majority of seats in
West Province, with 15 out of 25. it won one of these seats in a revote held for some constituencies on 15 September. In the
July 2007 parliamentary election, the SDF won 14 out of the 163 initially declared seats, These additional seats were crucial, because the SDF could not form a parliamentary group unless it had at least 15 seats. The party's electoral success remained largely confined to the Northwest Province, where it again won a majority of seats, with 11 out of 20. The SDF strongly opposed a constitutional amendment allowing Biya to run for president again in 2011. Its deputies boycotted the April 2008 parliamentary vote in which the amendment was approved, and it subsequently called for a "day of mourning" in which people were to wear black and stay home. One key alliance is between the SDF and the female
Takembeng mobilizations. These women provide protection for SDF officials and a key presence at SDF demonstrations. ==International affiliation==