Summary:
Rome, as a warrior state had won many fights in the past. Because of alliances, it gained more power which enabled it to expand its territories along Tiber Valley and southwards into Campania.
Paraphrase:
Rome was a country of fighters, its large dominion had been too powerful to defeat in ferocious battles. In the 4th century BC, It had become an insignificant city but it rose through collaborations with neighboring vicinities. Its various conquests led not only to the formation of its own country along the Tiber Valley but also to the enlargement of its dominion southwards into Campania. This was a system of a step-by-step progress and firm federation.