he was also a man that had long ago pacified the west, and made it subject to the Romans, when it had been put into disorder by the Germans; he had also recovered to them Britain by his arms, which had been little known before whereby he procured to his father Claudius to have a triumph bestowed on him without any sweat or labour of his own.
I'd associated Claudius himself with the conquest of Britain; as we see here, Claudius was already at the time taking credit for Vespasian's work.
The Romans have a reputation for making their roads dead straight, going straight over any hill in the way, rather than round them for easier travelling as other road-making cultures do. Amusingly, III.6 says (in Williamson's wording):
After them came the pioneeers to straighten out bends in the highway, level rough surfaces, and cut down obstructive woods, so that the army would not be exhausted by laborious marching.
(Whitston simply says "to make the road even and straight" rather than to straighten out bends; but I found Williamson's wording amusing.)
Skipping a good deal, after the Romans had retaken Galilee and the siege of Yotapata, from which the Romans had prevented Josephus escaping, had ended with the city's conquest and destruction, Josephus took refuge in a cave with some others, but a woman from his party was captured and gave away his location to the Romans. Those with him urge them all to commit suicide; in his argument against this, Josephus says some interesting things about the contemporary views on the afterlife, resurrection and suicide (III.8):
"Do not you know that those who depart out of this life according to the law of nature, and pay that debt which was received from God, when he that lent it us is pleased to require it back again, enjoy eternal fame; that their houses and their posterity are sure, that their souls are pure and obedient, and obtain a most holy place in heaven, from whence, in the revolutions of ages, they are again sent into pure bodies; while the souls of those whose hands have acted madly against themselves are received by the darkest place in Hades, and while God, who is their Father, punishes those that offend against either of them in their posterity? for which reason God hates such doings, and the crime is punished by our most wise legislator. Accordingly, our laws determine that the bodies of such as kill themselves should be exposed till the sun be set, without burial, although at the same time it be allowed by them to be lawful to bury our enemies [sooner]. The laws of other nations also enjoin such men's hands to be cut off when they are dead, which had been made use of in destroying themselves when alive, while they reckoned that as the body is alien from the soul, so is the hand alien from the body. It is therefore, my friends, a right thing to reason justly, and not add to the calamities which men bring upon us impiety towards our Creator. If we have a mind to preserve ourselves, let us do it; for to be preserved by those our enemies, to whom we have given so many demonstrations of our courage, is no way inglorious; but if we have a mind to die, it is good to die by the hand of those that have conquered us. For nay part, I will not run over to our enemies' quarters, in order to be a traitor to myself; for certainly I should then be much more foolish than those that deserted to the enemy, since they did it in order to save themselves, and I should do it for destruction, for my own destruction. However, I heartily wish the Romans may prove treacherous in this matter; for if, after their offer of their right hand for security, I be slain by them, I shall die cheerfully, and carry away with me the sense of their perfidiousness, as a consolation greater than victory itself."
When Josephus is taken prisoner, and brought before Vespasian, he says (III.9):
"Thou, O Vespasian, thinkest no more than that thou hast taken Josephus himself captive; but I come to thee as a messenger of greater tidings; for had not I been sent by God to thee, I knew what was the law of the Jews in this case? and how it becomes generals to die. Dost thou send me to Nero? For why? Are Nero's successors till they come to thee still alive? Thou, O Vespasian, art Caesar and emperor, thou, and this thy son. Bind me now still faster, and keep me for thyself, for thou, O Caesar, are not only lord over me, but over the land and the sea, and all mankind; and certainly I deserve to be kept in closer custody than I now am in, in order to be punished, if I rashly affirm any thing of God."
When he had said this, Vespasian at present did not believe him, but supposed that Josephus said this as a cunning trick, in order to his own preservation; but in a little time he was convinced, and believed what he said to be true, God himself erecting his expectations, so as to think of obtaining the empire, and by other signs fore-showing his advancement.
Given that R. Yoḥānān ben Zakkai would later say something similar to him when he too was taken before Vespasian, one wonders how much these two put the idea into Vespasian's head of proclaiming himself emperor, or of accepting it when his men tried to proclaim him such.