During World War II, he served as envoy to Oslo, where he remained until the German occupation, and later represented Sweden to the Norwegian government-in-exile in London.

In 1959, as Dag Hammarskjöld's personal representative, he successfully mediated the resumption of diplomatic relations between Thailand and Cambodia.

Beck-Friis also held numerous honorary positions, including chairman of several Swedish organizations, Grand Master of the Great Order of the Amaranth, and Chamberlain.

[1] His paternal grandfather was the officer, court marshal, and Member of Parliament Joachim Tawast Beck-Friis [sv] (1827–1888), and his maternal grandfather was Vice Admiral Carl Gustaf von Otter [sv] (1827–1900), who served as Sweden's Minister of Naval Defence from 1880 to 1892.

His brother Carl Beck-Friis [sv] (1886–1969) was a conservative Member of Parliament, officer, and estate owner.

The other brother, Ryttmästare Gustaf Joachim Beck-Friis (1886–1936), was CEO of the Swedish Farmers' Accident Insurance Company (Svenska Landbrukarnes Olycksfallsförsäkringsbolag).

[3] Following his discharge from military service on 29 August 1919, he was appointed second legation secretary at the Ministry for Foreign Affairs on 12 September 1919.

He was appointed chargé d'affaires ad interim in Athens on 11 November 1923 and later became the first legation secretary in Copenhagen on 28 June 1924.

Many of Beck-Friis's reports have been published in Sweden's white papers on the country's policy during World War II.

[1] In 1959, as Dag Hammarskjöld's personal representative, he successfully persuaded Thailand and Cambodia to resume diplomatic relations.

[1] Additionally, in 1956, he was named an honorary member of the Circolo Scandinavo in Rome, the first person to be honored in the association's then 97-year history.