The General Electoral Union pushed for 35 years as an upper limit for SNU members, as well as a formal understanding that the role of SNU was to recruit young people for the General Electoral Union.

SNU however refuted the idea of an age limit, as the organization wished to exert more political influence of its own.

In 1934, the small pro-German National Labour League (Nationella Arbetsförbundet) merged into SNUoF.

The same year the name was changed to National League of Sweden (Sveriges Nationella Förbund).

The following year, on October 10, 1937, the National League New Sweden of Per Engdahl merged into SNF.

At its national conference in 1938 SNF officially adopted a party programme, describing themselves as Corporative, New Swedish, Radical, Nationalist and Socialist.

Along with him left many prominent party members, like Ljungberg, and a major section of the youth wing.

The same year SNF began to receive financial support from the Nazi Germany to publish the newspaper Dagsposten from Stockholm.

When Christian Democratic Rally (KDS) emerged as a new political party in the 1960s, SNF tried to infiltrate it.