Pare Lorentz's The Plow that Broke the Plains (1936) and The River (1937) are landmark American documentary films. Aesthetically, they break new ground in seamlessly marrying pictorial imagery, symphonic music, and poetic free verse, all realized with supreme artistry. Ideologically, they indelibly encapsulate the strivings of Franklin Delano Roosevelt's New Deal.

The first film created by the United States Government for commercial release and distribution, The Plow was also – in the words of the film-music historian Neil Lerner – "the most widely publicized attempt by the federal government to communicate to its entire citizenry through a motion picture." It became the first film to be placed in Congressional archives and, following the wishes of FDR, would have become the first film screened at a joint session of Congress had the capitol chambers been equipped to show a sound film.

Virgil Thomson's scores for both films – here recorded in their entirety for the first time since Alexander Smallens conducted the soundtracks – are among the most famous ever composed for the movies. Aaron Copland praised the music for The Plow for its "frankness and openness of feeling," calling it "fresher, more simple, and more personal" than the Hollywood norm. He called the music for The River "a lesson in how to treat Americana."

The Plow that Broke the Plains was denounced (accurately) as New Deal propaganda. Sensing competition, Hollywood barred The Plow from its distribution system. Billed "The Picture They Dared Us to Show!" it opened at New York's Rialto Theatre and was cheered nightly. Public demand prevailed: eventually, over 3,000 theaters (out of 14,000 commercial cinemas nationally) screened The Plow to enthusiastic reviews. The Baltimore Sun found "more serious drama in this truthful record of the soil than in all the 'Covered Wagons' and 'Big Trails' produced by the commercial cinema."

Voted the best documentary at the 1938 Venice Film Festival (beating Leni Riefenstahl's Olympiad), The River was an overwhelming critical and commercial success. Paramount Pictures accepted it for national distribution. Lorentz's script, a Whitmanesque poem called by James Joyce "the most beautiful prose that I have heard in ten years," was nominated for a Pulitzer Prize.

The rationale for the present CD is obvious: the original thirties' soundtracks, gritty and opaque, do not do justice to Thomson's scores; more recently, this music has only been performed and recorded in the form of suites culled by Thomson, with many pages omitted.