In the ancient Greece of Pericles and Plato, the polis, or city—state, reigned supreme, but by the time of Alexander, nearly half of the mainland Greek city—states had surrendered part of their autonomy to join the larger political entities called koina. In the first book in fifty years to tackle the rise of these so—called Greek federal states, Emily Mackil charts a complex, fascinating map of how shared religious practices and long—standing economic interactions faciliated political cooperation and the emergence of a new kind of state. Mackil provides a detailed historical narrative spanning five centuries to contextualize her analyses, which focus on the three best—attested areas of mainland Greece—Boiotia, Achaia, and Aitolia. The analysis is supported by a dossier of Greek inscriptions, each text accompanied by an English translation and commentary.