Socii

The socii (['sokiː] in Classical Latin; ['sɔtʃiː] in Italian Latin; /ˈsoʊʃiaɪ/ in English; "allies") were the autonomous tribes and city-states of the Italian Peninsula in permanent military alliance with the Roman Republic until the Social War of 91–88 BC. After this conflict, all Rome's peninsular Italian allies were awarded Roman citizenship and their territories incorporated in the Roman state. The Romans themselves referred to their confederates as the socii Latini ("Latin allies"), although most were not members of the Latin tribe strictly speaking, but members of various other Italian tribes and city-states. In everyday usage, the word socius /ˈsoʊʃəs/ could mean "associate" or "partner" in general.

The alliance had its origin in the foedus Cassianum ("Treaty of Cassius", 493 BC) signed by the fledgling Roman republic with its neighbouring Latin city-states shortly after the overthrow of the Roman monarchy in 510 BC. This provided for mutual defence by the two parties on the basis of an equal contribution to the annual military levy, which was probably under Roman overall command. The terms of the treaty were probably more acceptable to the Latins than the previous type of Roman hegemony, that of the Tarquin kings, as the latter had probably required the payment of tribute and not a simple military obligation.

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