While still a student at Princeton in October 1956, he was granted access to the files gathered during Operation PBHistory by the US Central Intelligence Agency, and given permission to write a book about the events surrounding the 1954 Guatemalan coup d'état. Schneider wrote the book while he was a research assistant at the Foreign Policy Research Institute (FPRI), a think-tank in Philadelphia. After spending an initial six months with the PBHistory materials, Schneider also traveled to Guatemala and Mexico to further research his book, where he was assisted in his research by his wife. Schneider's book is likely to have been subsidized by the CIA, possibly without his knowledge. The book was described as a balanced presentation of the subject, and as "easily the most comprehensive and best documented work on that subject." It found no evidence that Guatemalan communism had been influenced by the Soviet Union. Despite being based on documents gathered by a CIA operation, the book did not attempt to justify the coup: Max Holland stated that it bore similarities to the work of Robert Alexander, who was critical of the policies pursued by the US in Guatemala.