Much to my own surprise, I found myself in the tech lead in 680AD thanks to a mixture of good planning and fortunate tech trades. Despite the poverty of my starting position, I was actually getting a good amount of commerce from the water tiles of the Mare Azteca, especially now that I had constructed the Colossus as well. Gibbon popped in a few turns later just to confirm what I had already determined from the tech trading screen.
Still #1; I expect Victoria and Mansa Musa to be the largest dangers long-term in the tech race. I had no clue why Caesar was so pathetically backwards; I later figured out that he was ravaged by barbarians at this point, but he would eventually manage to bounce back from that setback. Vicky is dominant in score, so she is probably the biggest threat overall. Religiously, you can also see that there is a Buddhist bloc (Mao and my Azteskimos) and a Jewish bloc (Saladin and Alexander). Caesar still didn't have a religion at this point, so I made a note to try and get him on my side as well with missionaries.
I hooked up my copper for the first time in 840AD. Hooray, now maybe I will survive for 10 seconds if Caesar decides to come after me. 
I also completed a rather important structure the same turn:
Great Library, very nice. I should get at least one Great Scientist out of this as well, which will definitely help out too. At about this same time, I managed to establish my first trade routes and get some resource exchanges going with the other civs; deer to Caesar for corn, fish to Vicky for gems. I basically had resource monopolies on deer, furs, and fish, which I could use to trade for useful stuff with the other AI civs. That was probably the only advantage to this tundra start, having resources that none of the other civs started out with.
When I discovered Feudalism in 960AD, I upgraded all my archers in exposed cities to longbows. I have no idea how successful that was in warding off AI aggression, but the peace still held for the moment. The cost was partially offset by selling Horseback Riding to backwards Caesar for 180g (see, there was a reason to trade for it after all!) I might end up regretting that if Caesar ran over me with Horse Archers later, but I figured that his Praetorians were more than strong enough to kill me already, so no harm done. Meanwhile, I was building Buddhist missionaries in Teotihuacan and sending them to Rome in order to get Caesar onto my side. The first one of these visited Rome in 980 and made a successful conversion. I reasoned it would take a couple more missionaries to get him to convert overall.
Here's the situation in 1000AD:
Looking at the minimap, you can see that several Chinese (and one Roman) cities have already been converted to Buddhism. Tlaxcala is the city that got me copper, but its land is so bad that it will never be able to grow past size 7. (I'll have more to say about this city later on.) At this point in time, I was moving some military into place to attack the barb city of Bantu (not pictured in the west), which would secure my western border and get me several more resources, including iron. Obviously there's no more room to expand further to the south; I was glad just to get the Tlatelolco site! Like I said earlier, if anyone manages to get the Nanjing site and be able to defend it, or take out Rome/China somehow, they will likely have some impressive results. There was also some room to expand to the east, but I hadn't scouted enough over there and wouldn't do quite as well in that area. More on that in a bit too.
By 1030AD, I had assembled my attack force outside the barb city of Bantu and prepared for the assault. Here's what the barb defense looked like:
Three archers, only one of them promoted, and a worker there for the taking. The city did have walls, but I have already bombarded them down with my cats. My first cat, promoted with City Raider I, goes in and actually wins its battle! City Raider II Jag follows and LOSES to an unpromoted archer! 
Well I guess the luck does balance out then. That archer won with 0.1 health left too, argh. City Raider I Jag kills the third archer, my other cat cleans up the crippled archer, and the city is mine:
The worker was a nice reward. Now since I hadn't found anything better to do with the free Great Artist that I received from discovering Music first, I decided that I would use him for a culture bomb here in Bantu to end the resistance instantly and establish a strong western border for my civ. I had brought the Artist along with my attack force, and so the culture bomb was detonated on the same turn, still in 1030AD:
That was a quick turnaround, wasn't it? From a barb city to the most cultured spot in my entire civ in one turn! 
Anyway, the new borders allowed me to spot a Roman Praetorian wandering around on barb duty. Just look at that health bar - yikes! I'd better make sure that I get Caesar on my side sooner rather than later. If you look at the score box in the corner, you can see that Caesar is actually Daoist at the moment. He only has that religion present in like two cities, but the LAST thing I need is a hostile Mansa Musa/Caesar alliance on my western border! No, I need to get him into the Buddhist camp instead. With that in mind, I continued a slow campaign of converting his cities with missionaries.
There's one picture of the process in action, here converting the city of Antium. Teotihuacan again drew grunt duty for my civ, mostly due to its location on the western side of my core. Those missionaries delayed the infrastructure of Teotihuacan, but the extra income in my capital/holy city came in handy. I was running Organized Religion so that I didn't have to bother with monasteries; with this shield-poor start, the building boost also was a serious advantage that I couldn't pass up! (Note that this was the very opposite of the Epic One situation that I played; rather than a large, sprawling empire I had a small and compact one with poor lands. Thus it was better to go with the stronger civics even if they carried an expensive price tag!)
The same turn that the above shot was taken I discovered Civil Service. Once again there was a tech trading opportunity at hand, and I shipped Civil Service to Alex for Machinery. Revolt to Bureaucracy! Obviously with my capital pulling in the bulk of my scientific research, that civic would be most beneficial for my Asteskimos. My third Great Prophet popped up in Tenochtitlan as well (d'oh, was hoping for a Scientist!) and I used him to knock out most of the research on Divine Right. 6 turns left for the remainder, which I began working on.
Trade Music to Mansa Musa for Optics in 1120AD. Whale time! 
(Of all the resources I expected to have on a Highlands map, WHALES was not one of them!) A couple turns later I get lucky and "pop another one" at Texcoco:
A native sources of gems, excellent. Settling the Texcoco site is already paying off. I bump up science by one tick to 90% in order to get Divine Right one turn sooner, thus resulting in this screen in 1150:
I found Islam, Teotihuacan becoming the holy city. That was nice and all, but I really could care less about this religion. Islam was doomed to become a niche minority religion, greatly overshadowed by the predominant Buddhism. I only founded the religion to prevent Mao or Caesar from grabbing it and messing up the alliance I was forming. Research into Guilds next - not to build knights (I still don't have horses!) but to open up grocers and the path to banks.
Calixtlahuaca was founded on the east side of the lake in 1210. There was actually some more good land to the east of that, but I didn't know about it and ended up moving too slowly to grab the region, which would fall to Saladin. Ah well. Instead, I was occupied at the moment with attacking a barb city called Etruscan that had appeared to the southeast of Tlatelolco. My leftover units from the attack on Bantu were slowly ported over there (literally on the opposite end of my territory!) and the siege began.
Once the walls were bombed down, I began the attack in 1260. Cat goes first and loses despite favorable odds (oh well), Jag kills archer, second cat kills other archer and takes the city!
The only problem: I now have a cat with like 0.5 health left, and two more barb archers right outside the city ready to take it back. I fully expect to lose the city, but for whatever reason the archers move away without attacking. HA! (They must have been programmed for city defense rather than city attack, that's the only thing I can thing of.) Got lucky again, but I'll take it here. 
Now it's a little hard to see here, but Etruscan is only three tiles away from a Chinese city to its west, and four tiles away from an Arab city to the east. It has great land, however, so if I can defend it (which is a bit doubtful) and get some culture in the city, it will be a MAJOR coup for my civilization. Also note the score display on the right side of the screen and the religious icons present in 1260AD.
That's because there was a major change that took place the following turn in 1270AD - Caesar has switched to my religion!
This is great news for me. Caesar's Rome and Mao's China are the only two civs close enough to me to have a legitimate chance of wiping out my civ. By converting them to my faith, I have erected a magical shield against harm from those two - who are otherwise often highly aggressive and dangerous opponents. This will allow me to run weak defense and rely on the goodwill of my neighbors to protect me, all the while pushing for a peaceful victory condition. Basically, I had no chance to win the game if one of those two came after me, so I had to do everything possible to get them on my side! I will be interested to see how others choose to manage the diplomatic side of things.
That picture also does a good job of showing how close Mao's Chinese city was to Etruscan. Only three tiles away, so there will definitely be a cultural battle there. Given that Etruscan is one of the few genuinely good cities that I have, however, it's one that I will gladly fight. I get a Great Scientist in Tenochtitlan in 1280, which I use for an Academy in the city. Beakers go from 57 per turn to 80/turn! The Great Library clearly had more than paid for the time needed to build it.
I finished researching Banking in 1290 and began Paper, heading towards Liberalism. I still have the tech lead, by the way; this Highlands map is so rough that I'm actually still ahead of the AI civs in terms of commerce thanks to my Colossus and use of the sea. I did NOT swap to Mercantilism, because almost all of my cities were on the coast and had harbors built. I was therefore almost certainly getting more use out of foreign trade routes and Open Borders than the AI civs were. After discovering Paper in 1320 and starting in on Education, I managed to trade Divine Right to Mansa Musa for Philosophy and 190g. THIS is why I used the Great Prophet to discover the tech - the path to Liberalism has now been cleared! I also sold Music to Mao for 210g and his world map, giving me my first real picture of the world. Here's a shot of the eastern part of the lake with the newly updated minimap:
That shows the location of Calix for the first time, which is another fishing colony with a little bit of production. On the minimap, it's now apparent that Caesar is to the west, Mao to the south, and Saladin to the east. Beyond them, on the southern border of the map from west to east, are Victoria, Mansa Musa, and Alex. Caesar has been backwards and way behind in score the whole game, but looking at the minimap now it's clear that he's going to get the entire northwest corner and become a giant down the road. Glad he's on my side!
By this point in time, most of the land on the map had been settled by one civ or another. It was therefore likely that the first major wars would begin breaking out - and sure enough, the first declaration took place on the very next turn in 1330. Go on to the next page to see where the action was starting up.
