In Alsace, the Popular Republican Union (UPR) was considered the URL's sister party.
The URL-URD evolved to become more of an electoral coalition rather than an organized political party, an evolution all too common in France at the time.
Despite the independence of its members, the URL maintained a strong base due to the support of the clergy, mayors, industrialists, and the media.
The UPL, UPR, and PDP merged in 1946 to the create the Popular Republican Movement (MRP).
In the Chamber of Deputies, the URL's parliamentarians sat with various groups from the centre-right and the right before forming, with the Alsatian UPR, the Republicans of the Centre in 1932 and the Independents of Popular Action in 1936.