Civilization V: The Celtic Chronicle, part 1 (4000 B.C. to 1150 B.C.)
A clash of generals
1750 B.C.: A French Great General arrives to defend Paris.
This levels the field a little. Previously, I'd been holding back French counter-attacks with my own Great General. Now that each side has one, the tide could turn quickly.
1725 B.C.: The French defenders sally forth from Paris with their Great General at the head of the army. The Picts besieging the city fall back to a nearby hill and make a stand there. The French are completely wiped out trying to take the hill, and the Great General is forced to flee south, through Paris and toward Lyon, to avoid capture.
Well, so much for the tide turning. By adjusting my line of battle very slightly, I was able to absorb the French counter-attack and leave them with no actual troops to defend the city. Great Generals can enhance an army's ability, but they can't fight on their own.
1550 B.C.: Barbarian warbands take advantage of the Celtic armies being away campaigning in France to raid the countryside around Edinburgh, taking civilians as slaves.
Ugh. This is what I get for not leaving any troops behind to fend off barbarians. I've lost my only Worker, which means I'll need to capture him back or build another one before I can continue building infrastructure like roads and farms--a very important task in the early game.