In Italy, the social sciences and humanities (SSH) have been constrained by a strong state regulation of academic recruitment and disciplinary contents and boundaries and a deep interpenetration between the academic field and political life. Governmental changes combined with pressures from different stakeholders led to a disordered proliferation of rules that were both constraining and manipulable. This institutional environment sets the stage for academic groups and resourceful academic men to act in order to strengthen their disciplines, expanding them while enforcing barriers and boundaries against other academic "tribes' and emerging disciplines. Quantitative and qualitative indicators (students; faculties; journals; professional associations) highlight how the interplay among field constraints, normative structures and collective actions shaped the post-1945 institutionalization of the seven disciplines under study.