It is the 90th anniversary of the BBC World Service. Broadcasting to countries behind the Iron Curtain without a free or independent media between 1947 and 1991 was arguably the service’s finest hour.

The corporation was on the front line of the information war as the BBC’s former Moscow correspondent Bridget Kendall recalls.

Programmes such as the German Service’s Letters Without Signatures created a sense of community among isolated East Germans who could not air their views publicly at home.

Meanwhile, Peter Udell, the former controller of European Services, had the challenge of trying to overcome the Soviet censors. Produced and presented by Josephine McDermott.

Archive recordings of former employees in the BBC Oral History Collection were used courtesy of Sussex University.

(Photo: A West Berlin policeman looks at an East German watchtower at night, 1961. Credit: Getty Images)