[1] The party was founded after the general elections of 2000 with the intention of bringing together the large numbers of people who had voted for Francisco Arias Cárdenas.

In the regional elections of 2004 the fracture within the party became increasingly evident, when Francisco Arias Cárdenas decided to start his candidacy for the governorship of Zulia and not support the alliance with Manuel Rosales, as well as the support for the official candidate Florencio Porras of the Fifth Republic Movement.

He also denied the victory of Hugo Chávez in the 2004 presidential recall referendum declaring that a fraud had taken place.

[2] However, after multiple compromises between Arias and Chávez, the Union became part of the government coalition, supporting the Fifth Republic Movement in all regional circuits.

At the end of December 2006, Union announced their dissolution and merger with the United Socialist Party of Venezuela.