A seminal innovation of the young Republic was the establishment, in c. 493 BC, of an indefinite military alliance with the other city-states of Old Latium, the home of the Latin tribe, to which the Romans themselves belonged. The so-called foedus Cassianum ("Treaty of Cassius") was a mutual non-aggression and defense pact. It required all signatories to assist any of their number who was attacked with all their forces. It also appears to have provided for joint operations in the field. Judging by the provision that the Romans and Latins were to share booty on an equal basis, it is likely that the treaty required the Latins to contribute roughly the same number of troops to joint operations as Rome. It appears that allied strategy was determined by an annual conference and that command of any joint forces may have alternated between Romans and allies.Dionysius I The treaty remained in force until 358 BC and effectively doubled Rome's military potential to c. 18,000 troops, a huge size for Italian armies of the time.
