1858 AD space win. Victory stats: Base score 6349 (final 77119). 38 cities giving me 7346 bpt research. Coming to the end of my 5th continuous golden age. Basically occupy the entire western half of the world, except for my vassals: Asoka, Suleiman, Peter and Charlemagne.
Asoka freely asked for my protection, the others succumbed in wars.
After 1AD I expanded peacefully to about 12 cities in 1350AD, using caste system to generate merchants to keep my science going. Looking back on it, I think I must have done something wrong there because that was an awfully slow expansion - and I didn't actually research that much either.
At that time, the land had all gone, and I declared war. The Ottomans first because of cultural pressure. Sadly, I ended up raising almost all their cities, apart from Istanbul - because they'd just about all been settled in what I thought were poor locations. Russia was next - around 1600AD. I picked Russia partly because the Mausoleum of Mausollos was in Moscow, and partly because Russian lands had tons and tons of unchopped trees, which I felt I could put to far better use. And finally, Charlemagne, in order to relieve cultural pressure on the previous Ottoman areas. In all cases, I reduced them to 1 city before accepting them as vassals.
A curious byproduct - aside from my getting lots of production once the trees were in my lands - was that this was virtually the first game in which I actually built and properly used the National Park. Usually it's useless for me because by the time I have biology and can build it, I don't have any trees left

But this time, I captured a Russian city - Rostov - with 10 forests still growing, and with biology already known!
I avoided any golden ages until I had the Mausoleum of Mausellos. By a stroke of luck, I built the Taj Mahal on the very same turn that Moscow, with the Mausoleum, came out of revolt. After that, I literally spent the entire rest of the game in near-continuous golden ages, thanks to all my accumulated great people plus the national park! That was rather nice, and I suspect went a long way to making up for my slow progress prior to 1300AD.
I noticed the AI seemed to be very bad at coping with this map. Asoka in particular still only had
one city by the end of the game. He did start in a very poor position - cut off by mountains and so needing a galley to build a second city - but even so, I was surprised he hadn't managed to do that by 1850AD! And then Peter was very bad at building improvements - it wasn't just those uncleared forests. I was capturing coastal cities around 1600AD to discover that he hadn't even put up fishing nets on his seafood!