"Hackers: Heroes of the Computer Revolution" (1984) by steven-levy is the definitive account of hacker-ethic-mit culture at the mit-ai-lab and other early computing centers. It is essential background for understanding stallman's formation as a programmer and activist.
stallman appears as a central figure in the MIT sections of the book, depicted as the last great hacker of the AI Lab era — a programmer of extraordinary skill and moral intensity who refused to accept proprietary enclosure of software. Levy's portrait captures both Stallman's technical abilities and the cultural isolation he experienced as the mit-ai-lab-hacker-culture-1971-1984 era gave way to commercial computing.
The "hacker ethic" that Levy articulates — information should be free, systems should be open, authority is no substitute for competence — is the cultural precursor to the four-freedoms and the free-software-definition. Stallman formalized this ethic into a legal and philosophical framework through the gnu-manifesto, gpl-v1, and the free-software-foundation.
The book was published in 1984, shortly after stallman had launched the gnu-project with the announcement-of-gnu-project. It is contemporaneous with the early founding-gnu-and-fsf-1983-1991 era, making it a near-contemporaneous document rather than retrospective history.
free-as-in-freedom-williams by sam-williams builds on Levy's account to trace Stallman's subsequent career. Together, the two books provide the full narrative arc from MIT hacker to free software founder.