Wodehouse was living in Le Touquet, France when the war broke out. In 1940 he and his wife were arrested and held at a camp in Tost, Germany. The book Wodehouse: A Life by Robert McCrum describes conditions at the camp as hardscrabble but livable. In his own letters he described life there as "governed by "rumors and potatoes." Red cross supplies supplemented short rations, but they weren't without amenities. He wrote the book Money in the Bank while interred. It was there he met Werner Plack, a Nazi propaganda official. Wodehouse agreed to record a set of five monologues describing his life in the camp. Whether it was said explicitly or implicitly these were not to be negative.Wodehouse was released under pressure from the propaganda ministry after much finagling in 1941. The timing surprised even him. He was taken by train to Berlin overnight.
Werner Plack paid Wodehouse 250 Reichsmarks for the five recordings. The first was broadcast June 28th 1941. Afterward friends sent warnings by telegram urging him to stop. his wife cabled "At all cost to ourself [sic] my darling please stop broadcasting." He continued anyway. The first two recordings were made in Berlin, and the other three he made while living Degenershausen in the province of Halle. He was driven back to Berlin twice more to make the last 3 recordings. Afterward, even lord Haw Haw called him a traitor. Northern Ireland banned his books. The BBC declared it would no longer broadcast his stories. The last three recordings were broadcast on the 23rd and 30th of July and August 6th in Germany. The Nazis re-broadcast them to England throughout August.
In the end his broadcasts were just mild descriptions of camp life. There was nothing particularly inflammatory about their contents. It was just that he had cooperated while his countrymen were under the blitz. Below is a typical sample:
"We had all pitched together, reverend elders and beardless boys alike... At Tost, the old dodders like myself lived the life of Reily. For us, the arduous side of life was limited to making our beds...When there was a man's work to be done, like hauling coal or shoveling snow, we just sat and looked on, swapping reminisces of the Victorian age, while the younger set snapped to it..."The recordings were aimed at America and the New York times reported that he would be broadcast once a week to the United States by arrangement with the German Foreign Office. The US was not yet at war making this possible. Before the broadcasts began, he was interviewed by Harry Flannery at CBS on air. The interview was the most damning of all.. he suggested that England might not win.
By 1945, MI6 records that he was “living at liberty in Paris”. In the UK the word outrage would be an understatement. Contemporary writers like A.A. Milne excoriated him. The best defense his allies had was to call him ideologically illiterate and naive. More here, here and here.