But closer relations than those of commerce might exist between Rome and states connected with her by neighbourhood or kindred. The interchange of the rights of private law, of ownership and of marriage, which the Greeks called ἰσοπολιτεία, was a natural out-growth of the Italian tendency to close political association. Such communion rendered each member of the contracting states in private law a _civis_ of the other; the _conubium_ carried with it the _patria potestas_ and all the family rights that flowed from this power; the _commercium_ allowed the citizen of the contracting state to own Roman land, to convey property by Roman forms, to make a contract by the ceremonial of the _sponsio_, to inherit from a Roman or to make a Roman his heir, while it gave the citizen of Rome corresponding rights in the alien city. There could be no question here of mixed tribunals or of private international law. The courts of each state were fully competent; if we may judge from the early relations of Rome with the Latin cities, the place in which the contract had been concluded, or, in other words, the forms of the contract, determined the competence of the court.[1402] Still more definite bonds of union than these relations of private law (although often their primary condition) were certain political creations which made the ties between the states something more than international. It was a nucleus approaching a federal government which gave the first impulse to the extension of Roman power in Italy. Rome, as known to us in legend, is never quite a city-state. She is an offshoot of Alba Longa, the titular head of the Latin league. Tradition says that her conquest of her mother city led to her occupying a singular position with respect to the thirty cities of this league. She was one of the contracting parties, the cities were the other; she was the equal, not the member, of the group. The acceptance of this position by the confederate cities shows their eagerness for the protection of the frontier town; but the protectorate became burdensome, a war ensued, and Roman rule was shaken off only to be reimposed on firmer lines by the strong hand of the Etruscan dynasty represented by the Tarquins. Rome now became one at least of the religious centres of the league, and the Diana of the Aventine symbolised the lasting union of the Latin folk.[1403] The expulsion of the kings, while it stripped Rome of territory, shook for a time the allegiance of the league, and it was not until 493 B.C. that the old conditions were renewed; for the details that might in historical times be read in the treaty attributed to Sp. Cassius were doubtless but a replica of the old terms of the alliance. Eternal peace was enjoined, mutual support was to be given in war, and each contracting party was to share equally in the booty. The supreme command in war was to be held now by the Roman general, now by the commander of the confederate