In 1931 he became interested in the Communist Party. He joined the party in 1934. He wrote for several Left-wing journals. These included "New Country", "The Left Review" and "New Writing". Upward's first novel was "Journey to the Border", published in 1938. At that time Upward was better known for a 1937 essay called "Sketch for a Marxist Interpretation of Literature". He wrote a trilogy called "The Spiral Ascent". The second part had trouble getting published. By the time the third part was published, it had to be underwritten by the Action Council. The council only agreed after pressure from Upward's friends. The three were titled "In the Thirties" (1962), "The Rotten Elements" (1969), and "No Home But the Struggle" (1977). The last two were almost completely ignored at the time. 