Joyce’s pre-war profile was sufficient to secure both him, and his wife, work as broadcasters for the Reichsrundfunks Foreign Service, the German equivalent of the BBC, based in Charlottenburg. The exact source of his sobriquet, ‘Lord Haw-Haw’, is not entirely clear, but most attribute it to Daily Express radio critic Jonah Barrington, who described a propaganda broadcaster as speaking “English of the haw-haw, damn-it-get-out-of-my-way variety, and his strong suit is gentlemanly indignation.”
Although the name was attributed to Joyce, the broadcast heard by Barrington was actually made by Norman Baillie-Stewart, a Sandhurst-educated officer whose voice sounded far more pompous than the American-Irish nasal twang of Joyce. As Joyce’s broadcasts gained in popularity the name stuck, and was soon exclusively associated with his broadcasts, with their signature cry of ‘Jairmany Calling! Jairmany Calling!’
At the height of his popularity, in the period up to the Battle of Britain, it was believed that up to 16 million British people tuned in to his Nazi propaganda broadcasts, an activity which, while not strictly illegal, was frowned upon by British authorities.
Joyce became the most important propaganda broadcaster in Germany at the time, and both he and his wife were granted naturalised German citizenship on 26 September 1940. With almost as many listeners as the BBC, he gained an almost mythical status: there were claims that he could forecast bomb targets, and that he knew intimate details about target sites: in reality, because of reporting restrictions placed on the BBC by the War Office, he could sometimes scoop the official stories by a few hours, releasing details before they could be broadcast officially, but this was the extent of his ability.
In contrast to his sinister broadcasts, his odd accent was a source of ridicule, and he was parodied by comedians, and even became the subject of some advertisements. But the joke soured with the onslaught of German bombing in Britain, and his popularity waned – though in Germany he remained as popular as ever, and in September 1944 he was awarded the Cross of War Merit First Class, by Hitler, for his broadcasting efforts.
His anti-Semitic stance never faltered, and he continued to blame the war on what he referred to as ‘Jewish International Finance’. He remained true to his belief that Germany and Britain needed to unite against the global Communist threat.
In addition to broadcasting, Joyce's duties included distributing propaganda among British prisoners of war, whom he tried to recruit into the British Free Corps, a branch of the Waffen SS. He also wrote a book comparing National Socialist Germany to the evils of a Jewish-dominated capitalist Britain, called ‘Twilight over England’, that was promoted by the German Ministry of Propaganda.
As the tide of war turned against Germany, Joyce began to drink heavily and his marriage soured. Both he and his wife, who took opium, in addition to also drinking heavily, became embroiled in numerous extramarital affairs.
In the final days of the war, with the Russian Army advancing inexorably towards Berlin, Joyce was forced to move to Hamburg to make his broadcasts, and his final transmission, during which he was clearly intoxicated, was made on 30 April 1945, in which he continued to rail against the Communist threat, and which he ended with a final, defiant ‘Heil Hitler!'
The following day Radio Hamburg was seized by advancing British forces, which made a final, mock "Germany Calling!" broadcast, denouncing Joyce, who had been forced to flee again, with his wife, this time north towards the Danish border.