The historian Gerhard Schøning from Lofoten in northern Norway had studied in Copenhagen and in 1751 was asked to be the headmaster of the Cathedral School by the former headmaster of the school, Benjamin Dass. P F Suhm was a nobleman without money, but with an intense desire for study; he therefore sought to marry a rich woman. Schøning and Suhm were good friends and they left Copenhagen together for Trondheim. Suhm succeeded in marrying Karen Angell, a daughter of a wealthy tradesman, Lorentz Angell, who had a wealthy brother, Thomas, with no children. In Trondheim Schøning and Suhm met each other for study twice a week, and they decided that Schøning should write the history of Norway and Suhm that of Denmark. In 1758 J E Gunnerus from Kristiania was appointed bishop in Trondheim.

After the death of Gunnerus, the Society had a period of decline in which it mostly handed out awards and supported scientific investigations rather than engaging in research.

The Society's activity was particularly great for the first 50 years with meetings and publications. In these years, the Society in Trondheim was the only scientific institution in the country. Natural history and archaeological gatherings were created and from the start a library was established. Well-known scientists from home and abroad were elected as members of the Society. Later, business ceased, but increased again from 1874 in connection with the adoption of new statutes.

The Society in Trondheim built a new building in 1866, but the collections were in a bad state. In 1874 there was a significant change when the Society decided to establish a museum. Its main task was to promote natural and cultural history, archaeology and history in general. A modern museum was established that was also a library. 'Vitenskapsmuseet' is today a part of the university in Trondheim and still has both cultural and natural history collections. The library is also a part of the university.

In 1926, the annual general meeting agreed to reorganise the scientific activities. The statutes regarding ordinary activities were once again revised and new ones introduced to pave the way for a scientific academy with elected members holding academic qualifications and reflect the needs of the scientific institution, the Museum, with its collections and library. Since 1926, the Society has therefore consisted of two sections, the Academy with its elected members and a separate elected board, and the Museum with its collections and library run by a board.

The purpose of The Royal Norwegian Society of Sciences and Letters is to promote scholarship by arranging lecture meetings, demonstrations and debates on scholarly topics; by disseminating scholarly knowledge to the general public; by supporting scholarly projects, financially or otherwise; by honouring and rewarding services to scholarship; by publishing scholarly papers; by keeping contact with academies abroad and by international collaboration.