Nor was it even now restricted to the territory on Rome's side of the mountains; the last war had shown but too clearly that the Roman rule over central Italy was only secured, if it reached from sea to sea.

The establishment of the Romans beyond the Apennines begins with the laying out of the strong fortress of Atria (Atri) in the year 465, on the northern slope of the Abruzzi towards the Picenian plain, not immediately on the coast and hence with Latin rights, but still near to the sea, and the keystone of the mighty wedge separating northern and southern Italy.
Of a similar nature and of still greater importance was the founding of Venusia (463), whither the unprecedented number of 20,000 colonists was conducted.

That city, founded at the boundary of Samnium, Apulia, and Lucania, on the great road between Tarentum and Samnium, in an uncommonly strong position, was destined as a curb to keep in check the surrounding tribes, and above all to interrupt the communications between the two most powerful enemies of Rome in southern Italy.
Beyond doubt at the same time the southern highway, which Appius Claudius had carried as far as Capua, was prolonged thence to Venusia.
Thus, at the close of the Samnite wars, the Roman domain closely compact--that is, consisting almost exclusively of communities with Roman or Latin rights--extended on the north to the Ciminian Forest, on the east to the Abruzzi and to the Adriatic, on the south as far as Capua, while the two advanced posts, Luceria and Venusia, established towards the east and south on the lines of communication of their opponents, isolated them on every side.

Rome was no longer merely the first, but was already the ruling power in the peninsula, when towards the end of the fifth century of the city those nations, which had been raised to supremacy in their respective lands by the favour of the gods and by their own capacity, began to come into contact in council and on the battle-field; and, as at Olympia the preliminary victors girt themselves for a second and more serious struggle, so on the larger arena of the nations, Carthage, Macedonia, and Rome now prepared for the final and decisive contest.
Notes for Book II Chapter VI 1.

It may not be superfluous to mention that our knowledge Archidamus and Alexander is derived from Greek annals, and that the synchronism between these and the Roman is in reference to the present epoch only approximately established.