The origins of the channel can be traced back to 21 March 1938, when the EIAR – which was to become Radio Audizioni Italiane (RAI) in 1944 – began transmitting a second, separately programmed radio service in major cities.
Following the end of World War II and reconstruction and improvement of the surviving transmitter network, radio broadcasting was reorganized (with effect from 3 November 1946) to provide two national channels covering most of the country. The first channel was known as the Rete Rossa (red network) and the second as the Rete Azzurra (blue network). These "neutral" names were chosen to imply that, while at any one time each channel aimed to provide programming of a contrasting style to that available on the other, the two channels were nominally equal in status and had an equally wide-ranging remit.
On 1 January 1952, as part of a move aimed at giving each of its channels a more distinctive "personality" – a cultural Terzo Programma (third programme) having already been added on 1 October 1950 – RAI renamed the Rete Azzurra as the Secondo Programma (second programme), later to become RAI Radio 2.