First of all, to all who have expressed interest in this story, I'm sorry. Civ4 got the better of me.
On to it then
In 350 BC Brennus called a meeting with his chiefs-of-staff. This was a new council of Jeeves’ design and consisted of Brennus, Molly and Jeeves. Publicly, it was meant to take some of the workload off the other advisors. However, after Jeeves had decided to rejoin his master, the council had used every opportunity to quart the together again, happy again union. So the real reason for having a council of councillors was to have a good discussion in peace and quite and then “propose” readily made policies to the official council. They had unwittingly discovered parliamentarism.
Brennus had called the meeting because the Celts were running out of room to expand and they still only controlled around 50% of the world.
Brennus wasn’t ready to admit defeat now he had his loyal friend and companion back at his side. “I know we can do it, it’ll just take some time. Sooner or later our scientists will discover ships with no attack capabilities.
Jeeves, although he had had 100 years to make an effort, had found it hard to shake his aquired gloomy look on life. “Sooner or later someone will attack us and it’ll most probably happen sooner than ships that can only defend”, he said. Molly, who had had 100 years to calm down, felt he blood boiling again. It made her head go pink and this time Jeeves saw the since and added hurriedly before comments were made about his weak back: “No, we got to make it happen on this continent. But how?”
Molly said: “Maybe we should try and go around our friends’ territories and discover new land?”
Jeeves sighed: “We know pretty much all there is to know of this continent. We’ve only got the high seas left so I vote we make a few ships and send them out. None of the others will notice.”
“NO!” Brennus reaction was forceful to say the least. “I
made the rules. I’ll only cheat myself if I don’t stick to them. There
has to be another way.”
“Not unless we can steal land from the others”, Jeeves sourly replied. Then a look of intense thinking was followed by a somewhat puzzled and bewildered look. And a wall-to-wall style smile covered his face. “Of course. We’ll steal land from the others.”
Brennus had noticed Jeeves expressions change so he knew there might be a possible solution that wouldn’t involve training military. He tried to get straight to the point, but was too confused about Jeeves newly found confidence, so he said: “Grmph?! But, but, but. I mean to say how?
“Follow me to Oporto”, Jeeves said.
“Oporto? But that’s Portuguese?”
“Not
in Oporto. We’ll meet outside the city.
Jeeves jumped up and set about his own mysterious ways.
Shortly after, on the fields outside Oporto, the three companions met up with each other.
“Now what?” Brennus was pretty excited.
“See that settler over there? Order him to found New Cataractonium!” He added: “Please.”
“But that’s too close to at least 3 other cities. We’ll just waste precious land that way.”
“Yes, but we’ll soon gain more land. Trust me”, Jeeves smiled.
“Ok. You there. Settle here! Understood?"
Brennus wasn't used to speaking to the man in the street, nor fields, as it were. He just made sure they understood him. Perhaps the question was a little redundant though. A dog would have understood him. Sure enough New Cataract was founded in 250 BC:
“Nothing happened?” Breenus was to obviously disappointed to even bother trying to hide it.
“Not now, no. Let’s camp out here for a while and see what happens shortly, though. We can toast our success. Finally, we’ve got wine."

Only 20 years later:
"Put all cities on settler production!" Brennus said. "I want every man, woman and child who can carry a backpack out there. We'll spam the lot of them with our cities."