"Fixed" Barbs
Sorry to hear the Germans were more aggressive in your game, Wacken; so far the main trade I've kept going is Furs for Dyes, in fact Otto has never asked to end it so it's been going for 100 turns or so.
I entered the MidAges in 510 BC; I'd managed to get Mono and Eng by trading Lit and the Government Techs to the Scientific AI, so I started out on Theology knowing that the AI would go for Feudalism first. There was only 1 GW left, the Great Wall. I decided to go for it first before a Cathedral; I figured at Emperor Wonders would be harder to get so I shouldn't pass up an opportunity, and if I could finish it before someone learned Feudalism I could tumble all those partial pre-builds making them start from scratch.
Didn't work; got the note that some of the civs had started on Sun-Tzu's. But I did complete Great Wall in 310 BC, and by first disbanding one of my 2 Warriors, cash rushed a Cathedral in 290 BC. Decided to build a Marketplace at this time, taking 4 turns, a Worker (maxed out at size 12 of course), and then on to Sistine Chapel as Theology was completed.
I still had Great Library working, and a lot of turns to complete Sistine Chapel, so I timed Education to finish the turn after Sistine Chapel completed, and saved some Gold for the rush. I figured I still had a bit of a production lead on the top AI cities, so I should finish SC safely, and I did in 260 AD, with a University cash-rushed in 270 AD (after short-rushing an 80 Gold Warrior). The Great Lib had given me Feudalism, Chivalry, Invention and Gunpowder in the meanting; Education shut it off, and I forgot to trade it at that time so the AI learned it on the same turn.
At this point in time my entire unit force consisted of 1 Warrior/1 Worker fortified in London and 1 Curragh off dodging Barbs. (Eventually they caught it and sank it.) On the bright side, I had no gold being spent on unit costs!
It would be good to start increasing my defenses, but I had to take a shot at Copernicus' Observatory first. 12 turns to research Astronomy, and 16 turns to complete the Observatory. Sun Tzu's had already been completed, so just Leonardo's was left. I received word of the AI starting on JS Bach's, so I knew there was no chance to try for that wonder. After about 8 turns, the research cost of Astronomy suddenly dropped to 1! The leading AI (Vikings and Sumerians) had learned Banking and Astronomy and traded it. I was able to buy Astronomy for 10 Gold from the Vikings, so I didn't need to worry about my pre-build, but I still needed 8 more turns and I had to hope a Leonardo's cascade didn't take out the Observatory. Well, it didn't, and I completed CO in 430 AD.
Now I started adding a few more units to my forces, a couple of LongBows, a Horsemen, etc. Meanwhile, I tried for Chemistry, and got beaten to it by the AI. Next, off to Physics, and that one I learned as a Monopoly! I picked up 6 Techs, including Democracy, and I was off to learn Free Artistry which no one knew. All the pre-builds had been completed by this time, and the AI were just a few turns into Magellan's and Smith's. I used Bank for a pre-build, and was beaten by a few turns to Free Artistry, so the switch went well. The AI beat me to both TofG and Mag, so I had reduced research costs. I completed Shakespeare's Theater and entered the IA on the same turn in 720 AD.
The AI have already built Smith's and Magellan's, and they've had enough turns on Newton's that I don't believe I have a shot at it. I tried something early on in the Middle Ages to stir things up - I declared on Sumeria and used Theology to get the Vikings, Dutch and Babylon allied. I tried to get Germany allied, but Otto had contact with nobody! Not even the French! (Spain is already gone in my game.) Well, all this alliances and trading of Luxuries failed badly; my trade lines were cut either by the Sumerians or by the Barbs. So not only do I have a really, really pissed Gilgamesh, I've also been getting some Annoyed looks from the Dutch and the Vikings, and I've had a difficult time trading since a number of 20 turn deals were broken by the trade lines being cut.
Here's my culture chart up to 720 AD:
4000 BC 1 cpt Palace
2750 BC 4 cpt Temple (2 Forest chops)
1650 BC 9 cpt Colossus
1350 BC 13 cpt Oracle
975 BC 15 cpt Museum of Masollos
925 BC 18 cpt Library (partial cash rush)
570 BC 27 cpt Great Library
550 BC 29 cpt Coliseum (short cash rush to Warrior; then cash rush to complete)
310 BC 35 cpt Great Wall (1138 Culture)
290 BC 38 cpt Cathedral (disband Warrior; cash rush with 1 Gold to spare)
260 AD 49 cpt Sistine Chapel
270 AD 53 cpt University (short rush Worker, then cash rush) (2358 Culture in London)
430 AD 63 cpt Copernicus' Observatory (3222 Culture in London)
720 AD 78 cpt Shakespeare's Theater (5134 Culture in London)