In 1927, some NSDAP workers in large factories, located mostly in the Berlin area, joined as an alternative to social democratic and Christian labor unions.

[2] It began to increase its membership by means of aggressive campaigns, which included both propaganda and violence, under the war-cry: "Hinein in die Betriebe!"

As a result of the "Hib" campaign, the NSBO increased its membership to only about 300,000 by the end of 1932,[2] while the Democratic and Christian labor unions had still well over 5 million members.

[6] The NSBO's methods then included using armed violence in order to offset a salary reduction in a particular factory.

[7] After all non-Nazi trade unions were outlawed by decree on 2 May 1933, the NSBO became the only official workers' organization in Germany.