This I considered to be the best starting-point, because in the first place, Aratus's book terminates just at this period and I had decided on taking up and carrying on the narrative of Greek affairs from the date at which he leaves off, and secondly because the period following on this date and included in my history coincides with my own and the preceding generation, so that I have been present at some of the events and have the testimony of eyewitnesses for others. It seemed to me indeed that if I comprised events of an earlier date, repeating mere hearsay evidence, I should be safe neither in my estimates nor in my assertions. But my chief reason for beginning at this date, was that Fortune had then so to speak rebuilt the world.
For Philip, son of Demetrius, being still quite a boy, had inherited the throne of <a class="linkToPlace" target="_blank" href="/place?placename=Macedonia&groupId=723&placeId=428">Macedonia</a>, Achaeus, the ruler of all Asia on this side of the Taurus, had now not only the state, but power of a king, Antiochus surnamed "The Great" who was still very young had but a short time previously, on the death of his brother Seleucus, succeeded him in <a class="linkToPlace" target="_blank" href="/place?placename=Syria&groupId=995&placeId=502">Syria</a>, Ariarathes at the same time had become king of <a class="linkToPlace" target="_blank" href="/place?placename=Cappadocia&groupId=435&placeId=343">Cappadocia</a>, and Ptolemy Philopator king of <a class="linkToPlace" target="_blank" href="/place?placename=Egypt&groupId=556&placeId=368">Egypt</a>, while not long afterwards began the reign of Lycurgus, king of <a class="linkToPlace" target="_blank" href="/place?placename=Sparta&groupId=660&placeId=1208">Sparta</a>. The Carthaginians also had but recently appointed Hannibal to be their general in the campaign I mentioned. Since therefore the personalities of the rulers were everywhere new, it was evident that a new series of events would begin, this being the natural and usual consequence. And such indeed was the case; for the Romans and Carthaginians now entered on the war I mentioned, Antiochus and Ptolemy on that for <a class="linkToPlace" target="_blank" href="/place?placename=Coele-Syria&groupId=484&placeId=908">Coele-Syria</a>, and the Achaeans and Philip on that against the Aetolians and Spartans.
Walbank Commentary