it was founded in oslo in 1947. the organisation's first secretary-general was jurist trygve de lange. it fought against the regulation politics of the labour party, and had considerable influence on conservatives in the 1950s and 1960s. it held lectures at elingård in fredrikstad from 1948, and published the magazine "nå" from 1952 to 1995. libertas was succeeded by the liberal research institute in 1988.