Chapter 1 introduces the book’s main protagonists, the Islamic Revolutionary Guard Corps (IRGC) or Sepah, Corps. It examines the Sepah’s emergence, formal establishment, mission and duties, early institutionalization, and role in fighting counter-revolutionary and ethnic separatist groups. It traces how the Sepah formed from groups brought together by the shared goal of protecting what they saw as the revolution’s most important principles. It emerged in the days after Ayatollah Khomeini’s return to Iran on February 1, 1979 and in the midst of the Islamic Revolution’s turbulent and precarious transitory phase, which was characterized by political and violent struggles over the nature of the new regime. A particularly contentious issue, and one especially critical in the Sepah’s formation, was the fate of the Artesh, Iran’s regular military, and the nature of military power in the new regime.