 He was employed by the State Entomological Institution from 1903 to 1906 and at the National Museum at different times between 1903 and 1910 during which time he was a master at several higher schools in Stockholm from 1907 until 1909, and travelled in Sweden for study purposes through 1902 to 1909 before he led expeditions to Australia.A lecture tour in the USA lasted from 1916 to 1917 after which he was Swedish consul in Sumatra in 1920 among other postings and a study period in the US from 1921 to 1925.In the early 1900s Mjöberg set off to the Kimberley region of Western Australia in an attempt to prove his Darwinian human evolution theory.