The UDF was founded in 1978 as an electoral alliance to support President Valéry Giscard d'Estaing in order to counterbalance the Gaullist preponderance over the French centre-right.

In 2002 the RPR, DL and most of the remaining UDF members joined the Union for a Popular Movement (UMP), which aimed to unite the entire centre-right.

Two years later, Prime Minister Jacques Chirac (UDR) resigned and launched the Rally for the Republic (RPR), in order to restore the Gaullist domination over the centre-right.

The RPR would represent the right-wing of the presidential majority and would criticise with virulence the policies put forward by President Giscard and Prime Minister Raymond Barre.

Contrary to the RPR, the UDF advocated less market interventionism by the state, decentralisation and support of local authorities, and a strong commitment towards the building of a federal Europe.

Since the UDF list, led by Simone Veil, obtained 27.1% of the vote compared with RPR's 16.3%, the quarrels between the two parties and the rivalry between Giscard and Chirac contributed to the defeat of the incumbent president who ran for a second term.

were contested by a new generation of politicians called the "renovation men", who accused the old guard leadership of bearing responsibility for the successive electoral defeats.

In the aftermath, the CDS merged with the PSD into Democratic Force (FD), while CPR members and other supporters of Giscard within the PR formed the Popular Party for French Democracy (PPDF).

Bayrou subsequently refused Chirac's invitation to join the newly-formed centre-right, big-tent Union for a Popular Movement (UMP) for the upcoming 2002 legislative election.

Other UDF members, led by Giscard, Barrot, Douste-Blazy, Méhaignerie and Raffarin, as well as the entire PPDF and DL, joined the UMP, leaving Bayrou somewhat isolated.

After the election, the UDF, whose parliamentary seats were quite reduced, joined the victorious UMP as a partner in the government of Prime Minister Raffarin.

The UDF eft the government, except for Gilles de Robien, only after a cabinet reshuffle in March 2004, but still decided to remain in the parliamentary majority coalition.

There developed a split among UDF elected officials, between those such as de Robien and Pierre-Christophe Baguet, who favored closer ties with the UMP, and those such as Bayrou who advocate independent centrist policies, while others such as Jean Dionis du Séjour tried steering for a middle course.

In May 2006 Bayrou and other ten UDF deputies, a minority within the parliamentary party, voted for the motion of no-confidence brought forward by the Socialist-led opposition calling for the resignation of Prime Minister Dominique de Villepin's government, embroiled in the Clearstream affair.

In April 2007 Bayrou announced that he would be submitting a plan to a vote by UDF members to create a new Democratic Movement (MoDem), which was finally launched in May.

However, most of the UDF's deputies protested and formed the New Centre (NC) – later The Centrists –, in order to support newly-elected President Nicolas Sarkozy of the UMP.

During the 2007 presidential electoral campaign, François Bayrou presented himself as a centrist and a social-liberal[21] (he even opened the door to gay adoptions),[22] proclaiming that if elected, he would "govern beyond the left-right divide".

[25] The others, comprising members of Society in Movement and some Bayrouistes, as Hervé Morin and Jean-Louis Bourlanges, joined the presidential majority in support of the new President Nicolas Sarkozy and formed a new "centrist pole" within it, the New Centre.