de bello gallico, 4.27

The enemy having been conquered in battle, as soon as they recovered themselves from flight, immediately sent envoys about peace to Caesar; they promised that they would give hostages and they would do whatever Caesar had ordered. Together with these envoys, came Commius Atrebas, whom I had mentioned above, having been sent ahead into Britain by Caesar. This man, having gotten off the ship, when in the manner of an ambassador carried to them the orders of Caesar, those men had seized and thrown into chains: then they sent (him) back, with the battle having been finished. In seeking peace they threw the blame of this affair onto the multitude, and they asked that it be pardoned on account of ignorance. Caesar, having been asked, because they had waged war without cause, although on their own accord, with legates having been sent to the continent, they had sought peace from him, said he would forgive their ignorance and demanded hostages. Of which those men they gave part immediately, and part, summoned from more remote places, they said they would give in a few days. Meanwhile they ordered their men to move back into the fields and their chiefs began to come together from everywhere and entrust themselves and their states to Caesar.