In 1869 Hazelius was the secretary of the Swedish section at the Scandinavian orthographic congress in Stockholm (det nordiska rättstavningsmötet), and published its proceedings in 1871.

This gave Johan Erik Rydqvist (1800–1877) the energy to publish Svenska Akademiens Ordlista (SAOL), the very conservative first edition of the Academy's one-volume spelling dictionary in 1874.

[1][5] Hazelius was close friends with Swedish pathologist Axel Key, with whom he shared a number of common interests and helped found the museum.

– from all over Sweden and the other Nordic countries; he was mainly interested in peasant culture but his successors increasingly started to collect objects reflecting bourgeois and urban lifestyles as well.

Although the project did not initially get the government funding he had hoped, Hazelius received widespread support and donations, and by 1898 the Society for the promotion of the Nordic Museum (Samfundet för Nordiska Museets främjande) had 4,525 members.