Just finished a game in 1988. It is incredibly annoying getting an AI to go legendary. And then, as if to mock me, another AI's city went legendary before either of my PA civ's. Now to improve on that date (and there is a LOT of room for improvement).
beaten
1951 for me.
I didn't know you could settle GAs after a permanent alliance, so I wasted 10 or so GAs by gifting them to gandhi.
Well, he didn't send them to hell, he lightbulbed them all obviously.
This gave him nationalism before liberalism, and a helluvah lot of techs (DR for instance), and he was board leader for ever after that.
edit : I see fiveaces is ahead. No wonder, if you ask me

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A few random thoughts about what went right and what not :
- selecting only gandhi as industrial allowed him to build most wonders (the few he missed where those I built)
- I think gandhi is the best choice for a PA because 1) he's peaceful and doesn't care if you don't give in to his demands 2) he's industrious (vanilla), and goes quite happily after early wonders 3) he's spiritual, and doesn't refuse to build a few cathedrals
- selecting only "loyal" AIs made my world the most peaceful place you could think of (= no war, not even a smallish one)
- knowing from the scratch with whom you're going to PA makes it really trivial to get the PA when the time is right (a few gifts, a few resources, giving in to demands et voila, no need for shared religion)
- helping your target PA too early can have a cost. Gandhi beat me to liberalism!

at noble ! Not everything was lost, since I could sign a defensive pact with him before I had military tradition (he had it already!).
- I spread religions across Gandhi's cities to allow him to build more than 1 cathedral, and that worked.
- OCC is rather unusual for me, but a lot fun and easy to play. Health is a big problem, while happiness isn't.
- Gifting GAs to the AI early isn't a very bright move. I thought that if I gifted him 3 GAs in one city and 2 in the other he could not do anything else than settle them there. He obviously didn't. Lightbulbs don't have quite the same value.
- I played saladin. Philo is very valuable. Spiritual too, for diplomatic issues.Good choice, but maybe not the best? Playing gandhi could be good too, but that makes it impossible to play "against"/with him.