Many of Grierson's disciples were young, ambitious filmmakers from well-to-do backgrounds - Edgar Anstey, Harry Watt, Basil Wright and (most famously) Humphrey Jennings. The movement began under the auspices of the Empire Marketing Board, a government-sponsored organization charged with the responsibility of providing propagandist films both inside and outside the country. Grierson himself was a civil servant. From such beginnings grew an approach to filming that concentrated on ordinary people's lives; for the first time their work and leisure existences were filmed without condescension. The films themselves were highly successful and had the effect of drawing the nation together during turbulent times in the wake of the Great Depression.
In the mid-Thirties the Empire Marketing Board was closed down and the unit was shifted under the auspices of the General Post Office (GPO). One of their most notable releases was NIGHT MAIL (1935), a memorable representation the the night-train from Glasgow to London, and how it shifted mail from place to place in a feat of technology that could be perceived as the Thirties' information super-highway. With a poetic script penned by W. H. Auden and music by Benjamin Britten, the film was another huge hit.
By the outbreak of World War II the unit had been shifted once more; now it was controlled by the Ministry of Information and renamed the Crown Film Unit. In turbulent times it enjoyed its greatest successes, with memorable work such as Britain CAN TAKE IT (1940), and A DIARY FOR TIMOTHY (1945), both of which recorded the reactions of ordinary people to the turbulent effects (and after-effects) of war. Humphrey Jennings emerged as one of the greatest talents of the unit, with a unique ability to find poetic imagery in the most mundane material.
By the early Fifties the unit had virtually ceased to function. Jennings died prematurely after falling off a cliff; Watt moved into mainstream film production; while the others continued to make films but failed to make the leap into television. Nonetheless the unit's work remains as a living testament to the ways in which Britain adopted a socialist spirit in the purest sense of the term, with people of different classes collaborating - perhaps for the only time in the country's history - during periods of social upheaval.