To work his way upwards in society, he studied economics on his own, took voice classes from an actress to be a better orator, and was active in his trade union.

He chaired Kristiania faglige samorg from 1908 to 1913,[2] and was the deputy leader of the Confederation of Trade Unions from 1908 to 1910, later secretary from 1911 to 1915.

[1][2] In the 1912 general election, Iversen was fielded as Labour's deputy candidate in the constituency Gamle Aker, as running mate of Gustav Adolf Lammers Heiberg.

[4] In the 1915 general election, Iversen was fielded as Labour's deputy candidate in the constituency Gamle Aker, as running mate of Per Kviberg.

[8] From 1915 to 1941 he had his daytime job in the municipal administration of Oslo; he was fired because of the occupation of Norway by Nazi Germany and was then a member of the leading resistance circle Kretsen/Hjemmefrontens Ledelse.