[2] Hansen joined both the Social Democratic Party (SPD) and, in 1926, the Zentralverband der Angestellten (ZdA), a white collar trades union.
On the home front the British government reacted by identifying several thousand refugees who had fled Germany to escape race-based and political persecution as enemy aliens and arresting them.
[2] He spent the rest of the war in England, politically active with other exiled German socialist activists, working closely with Willi Eichler,[3] like him the son of a postal worker.
[2] One of the first of the political exiles to return, he made his way to Cologne, designated as part of the British occupation zone following a full invasion of Germany, and met up with fellow trades unionist Hans Böckler.
During the next few years, supported by the occupying forces, he set about reconstructing the trades union structure in the historically industrial Rhineland region.
[2] Hansen was a secularist who believed, in the words of one Christian contemporary, that the DGB should operate as "the extended arm of the Social Democratic Party (SPD)".