| Native Name: | Union Démocratique Dahoméenne |
| Leader: | Justin Ahomadegbé |
| Foundation: | 1955 |
| Country: | Benin |
| Banned: | 11 April 1961 |
| Merger: | Dahomeyean Progressive Union African People's Bloc |
The Dahomeyan Democratic Union (French: Union Démocratique Dahoméenne, UDD) was a political party in French Dahomey.
The UDD was established in 1955 by a merger of the Dahomeyan Progressive Union (UPD) and the African People's Bloc (BPA).[1] It aimed to be a nationwide party, but despite initially gaining support from across the country,[2] it quickly became identified as the party of the Fon of Abomey and Cotonou.
The party failed to win a seat in the French National Assembly in the 1956 elections, and split into two factions later in the year over the issue of affiliation with the African Democratic Rally (RDA); former BPA leader Justin Ahomadégbé-Tomêtin became head of the dominant RDA faction, whilst Alexandre Adandé and former UPD leader Émile Derlin Zinsou headed the smaller UDD-Convention.[3]
Despite its internal problems and regionalised support base, the UDD emerged as the second-largest party in the 1957 Territorial Assembly elections, winning seven seats. However, the 1959 elections produced an unbalanced result; although the UDD received 44% of the vote, more than any other party, it won just 11 of the 70 seats in the Territorial Assembly, whilst the Dahomeyan Democratic Rally (RDD) won 22 seats with 17% of the vote and the Republican Party of Dahomey (PRD) took 37 seats, more than three times the number of the UDD.[4] Following the elections, accusations of fraud led to an agreement being reached with the PRD to redistribute nine seats.[4] Although this increased the UDD's seat tally to 20, it was still the smallest party in the Assembly.[5]
In elections held the following year, the Dahomeyan Unity Party, a merger of the PRD and the RDD, won every seat after President Hubert Maga changed the electoral system,[6] leaving the UDD without parliamentary representation. Following the elections, the UDD was banned on 11 April 1961 and Ahomadégbé-Tomêtin was imprisoned.[7]