This was such an interesting map for many reasons - I myself won conquest t261 (1755AD) with tanks, nukes, and bombers. I settled my capital a bit later than you, spending a turn walking to the wheat. I think this made a massive difference because whether you settle on t0 or not
changes the seed to completely alter the direction of the game - in my game, Brennus started a lovefest by founding Hinduism, which became a serious problem later on as all the 3 on the continent had the same favorite civic too. It also changes which directions AIs walk their settler, which is huge for obvious reasons. Reloading or restarting the game or even your laptop does not change the seed, but small things like pillaging a tile or choosing to whip or completing a wonder one turn early/late can have huge snowballing effects...even if you haven't met anyone yet.
That being said, in my game, Brennus had no metal…unless he settles his third city very quick in a specific location, Hatty takes up like 3 iron, leaving him weak to Surry if he ever decides to attack with swords or something.
From looking at the replay at the end, that was what happened in your game too. I was able to exploit this by attacking him first, and despite being advanced in tech and having steel like me (I managed to lib it), he couldn’t build cannons (or knights or cuirs or any melee units)…near the end of the war he was whipping archers and horse archers vs rifles and cannons, lol. Surry also was confined to 4 cities, and Hatty…decided to go culture before rifling, so she was easy pickings. The game was definitely sealed after Hammy went fission and then radio without ever touching rifling or steel, at which point I became an unstoppable monster having taken 4 AIs.
There was a lot of variation between our early game strategy as well. I founded Mutal to take advantage of the wheat and grass cow, to maximize food, which was excellent for early and mid-game commerce but made it absolutely garbage for lategame production. I didn't even bother with Oxford, as it would've taken a million years to build (off-river means no levee, and I was too busy whipping/drafting to even care about universities).
However, for city#2, I founded Lakamha in this gigachad spot.
This city struggled with food all game but was absolutely
loaded with production. I chose to go for an early Oracle, beacuse Pacal starting with mysticism gave him an edge in teching the priesthood path (just 2 cheap techs that combined are only slightly more expensive than literally bronze working itself), and also me needing monarchy meant I lose nothing because I needed meditation -> priesthood for that anyways. With a grass copper and plains cow, Lakamha handily pumped that out, and I even went on to later
7-turn Colossus there because I had nothing better to build! The water tiles benefit only lasted 10-15 turns, before astro, but it was wild to work 6 food 3 commerce ocean fish for a bit. Perhaps the more crucial factor, however, was denying these wonders to the AI. AIs that get Oracle tend to use it on metal casting and then immediately build Colossus afterwards, leading to them being absolute runaways. Saladin likely would've gotten both were it not for me, leading to him becoming even more of a monster than he was in both our games. The great person points were also key to helping generate a GS to bulb edu, and then later a final GA to start one final late-game golden age, along with another GM. Last but certainly not least, I kept a lot of the forests around the city, and was able to nab Heroic Epic with a helpful warrior who won some early combats to reach combat2/cover. I libbed steel and went for rifling immediately after. With said forests, I rapidly chopped out an army of cannons and rifles when the time came in rapid succession, allowing me to attack Brennus t181 (1210AD!) with rifles and cannons, when he had neither (he had steel, but...me DOWing cut off all his metal access).
Honestly, after this game, I'm never underestimating the production power of plains cow again - a city working 2 plains cows for production, produced the oracle, the colossus, and most of my military over the course of 2000 years. Imagine getting destroyed because of dozens of tanks made from COWS. Nuclear weapons? built from organic steak, of course!
I settled the other cities to maximize food, in particular targeting the ocean fish that you orphaned for its long-term unitspamming potential. In particular, I whipped and drafted as much as possible as soon as steel/rifling came in, with nationhood. Draft rifles were crap, but speed was of the utmost essence, and even unpromoted rifles dealt well with
horse archers and longbows (without metal, that was all Brennus had...).
After seeing your endgame summary, I opened debug mode for the stats. It seems we were roughly on tech parity for most of the game, but near 1090AD (aboooout when we both got lib, in my case libbing steel), you started to pull far ahead in beaker rate while I pulled ahead in certain techs acquired. That was because I traded extremely aggressively. The diplo situation was not very favorable to me, unlike your game. Charlie and Hammy married each other as fellow Buddhists instead of fighting, and there was the aforementioned Hindu lovefest on Brennus's continent. With so many friendly faces, anyone getting a tech meant the others were going to get it anyways, monopoly or not, which meant I was more than happy to give away expensive things since I had no choice; the other AIs would get it regardless. When Surry researched astro, I immediately pawned it off to Hatty and Brennus for guilds, engineering, and music (otherwise, he would've just sold it for gunpowder/chem or something, which is what Brennus went for). After Brennus and I both got steel, giving it to Surry for scientific method for an almost 1:1 trade was a no-brainer. In a stroke of luck, Hatty switched to free speech/religion just before I declared on Brennus (perhaps the only diplo break I got this game), instantly dropping her to annoyed and letting me bribe her on him with steel. My rationale was that I would rather face her cannons later and in exchange get some help against Brennus immediately, and perhaps most importantly, break up the lovefest - as soon after, Brennus bribed Surry on Hatty, and the polycule was violently shattered via my machinations.
The other thing to note was that, I reached optics 2 turns later than you BUT I bulbed astro quite a bit earlier. This was because I didn't spend a GS on an academy, which IMO is usually not worth it in iso games unless your capital is god-like and/or you are PHI. Missing out on trades and getting left in the dust is far, far more disastrous than optics a bit slower, and if you muddle your great person pool with things like wonders and forges then you run the risk of a catastrophic low-odds great prophet or something. Of course, this is mitigated with reloading, but great person generation is actually
not affected by changing things like whipping, which means you cannot change the seed to turn your GP into a GS so easily. And, without reloading, your fate is truly left to the gods.
You can see the danger inherent in my save and the need for me to attack quickly by my debug demos at that date, which shows me about 150-200 bpt behind you in a golden age, and the other AIs 150-200bpt ahead of how they were in your game. Funny enough, I was still #1 in bpt rate, though not for long.
I guess the only
unlucky thing that happened in your game was Saladin popping both gems AND silver at/near his capital...the odds of that, quite literally, approach as small as 1 in a million - especially considering as those were the mining happiness/commerce resources that he happened to not have and which there existed only 1-2 copies through the world. In my game he "only" had his quintuple gold, so he wasn't quite as insane as he was in your save.
In future deity iso games, you may not get as fortunate as you were here, and I think it's best to maximize the food/power tiles you settle to prepare for a long, tough, uphill game where every single pop point and hammer matters. That's why I made the choice to go out of my way to not orphan the plains cow, copper, and ocean fish tiles, despite them perhaps being awkward to acquire early game.
All in all, very interesting and fun, and thanks for the map!
: Drink a bottle of Vodka before your every combat in BTS! 
<-- 
: Don't get drunk. Just don't 
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-resource, that's still a gold start. I think the play was just strategically very bad. There is a massive floodplain area directly to the south, so the most important thing must be to grab it asap and divide the fps between two cities. Going for Oracle is just absurd imo. Though I guess if stone was revealed some turns earlier that wouldn't have been the direction Henrik went, rather expand normally and get Mids later. But I think this was a good reminder for people how expansion is much more important than building wonders with a small number of cities. Grabbing the floodplains, building Mids the only issue is getting declared on by the southern neighbor.
from coal. There are many things that "only Tokugawa can do this!" "only Toku can play like this!" 
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victory, so expanding beyond 3 cities is just a waste"
. But that's wrong thinking. Having 8 or10 cities in 1AD is much better than building wonders with 3 cities.
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- because Ivory is gone. My Ivory trades with AI's resources are automatically cancelled as well. Same for Fur after Plastics. Many human players pay attention to the details more often in a horrible game (AP defy anger, war weariness, fall behind in techs, stack wiped out by AIs, getting dogpiled...) than in a good game. 
(namely all the wonders except shrines and corporations), and win culture. SMethods is required for Physics - Electricity and Broadway. That's how I know the 
. (As result, I often got DoW at Warlord level because I was under 100% 
