I've knocked out two space wins with Persia now (along with a number of failures), both on Emperor/Continents/Standard Map/Standard Speed. First attempt I won on turn 303 (1866 AD), second on turn 305 (1870 AD).
I like Persia for the space win because of the rockin golden ages. That extra boost of gold and production is critical for quickly building/buying up all that late game infrastructure (factories, solar plants, hydro plants, spaceship factories) and buying up city states for food/culture. With 100% longer golden ages (50% from UA, 50% from the wonder), I was able to stay in a permanent golden age from the about the 1400's all the way to the very end (triggered the start of it with happy faces, then kept it extended with Taj Mahal, Rationalism social policy, and burning non-scientist great people). Without the massive amounts of gold and production boost you get from GA's, I wouldn't be able to get all that infrastructure built in time, because once you hit Steam Power for factories, the game starts moving really fast and those structure require a lot of hammers. With the cash from golden ages, I'm able to buy about half the infrastructure, and use the rest on city states (I had 9 city states at Ally status by the end of my latest game).
I find that a few things are really key for a quick space victory. First, KILL (OR SEVERELY MAIM) YOUR NEIGHBORS! And do it early. There is basically NO chance that they aren't going to cause you trouble down the line if you don't. Either they get tired of you and declare war on you, or if they are too scared to fight you directly, then they will go on a rampage and kill every city state in sight, which is just as problematic. If it doesn't come down to war, you simply need the land anyways, and you won't be able to settle enough land on your own for a fast win (rex'ing hard in the beginning will undoubtedly cause them to declare on you anyways). In my second game, I went after Napoleon immediately since he's always a blood thirsty war monger, but left Lizzy alone. This was a mistake, because as soon as she hit longbows, she went and conquered 4 city states before I could muster up enough troops to shut her down. This cost me at least 10-15 turns off my victory time, maybe more.
Second, research agreements are important. Once you hit the start of your massive golden age and start raking in the dough, start making research agreements with EVERYONE. My second game (1870 AD win) should have ended much faster, but unfortunately Hiawatha had conquered EVERYONE on the other continent by then, and both Lizzy and Ghandi (on my continent) were too poor to ever make agreements with me. Some of the agreements would undoubtedly give me useless techs from the bottom of the tree, but I could have shaved off another 10+ turns at least if I had a few trading partners.
Third, great scientists are even more important. This is another area where I screwed up and it cost me a good number of turns in my second attempt. I only managed a total 6 great scientists. If I had planned it better I suspect I could have gotten about 8-10. Save these guys till the end, and use them to blow through the final part of the tech tree. First thing you do is get about 2-4 techs away from Rocketry, the pre-req for Apollo program (beeline it right after Steam Power and Railroad). Blow some scientists (and/or the final policy in the Rationalism tree, which gives two free techs) to get to it quickly, and start building it in your highest production city. Now start on the rest of the top of the tree. While you are building the Apollo Program, you can research another 3-4 techs. You are going to be about 12-14 away from the final spaceship part tech (Nanotechnology), so if you have a good number of GS's saved up and a get few lucky Research agreements, you can finish Nanotechnology within a few turns of the Apollo Program. By now you should have your production infrastructure in place, and should be able to finish off the spaceship parts in less than 30 turns.
That's about all I've got for now. I think Persia is the best candidate for quick space wins for all of the reasons above. Babylon may be good as well, but I don't have them so I can't test it out. If you do everything right, I think a pre-1800's win is very possible.
Feel free to add your own tips or other strategies, or to comment or ask questions about mine.
I like Persia for the space win because of the rockin golden ages. That extra boost of gold and production is critical for quickly building/buying up all that late game infrastructure (factories, solar plants, hydro plants, spaceship factories) and buying up city states for food/culture. With 100% longer golden ages (50% from UA, 50% from the wonder), I was able to stay in a permanent golden age from the about the 1400's all the way to the very end (triggered the start of it with happy faces, then kept it extended with Taj Mahal, Rationalism social policy, and burning non-scientist great people). Without the massive amounts of gold and production boost you get from GA's, I wouldn't be able to get all that infrastructure built in time, because once you hit Steam Power for factories, the game starts moving really fast and those structure require a lot of hammers. With the cash from golden ages, I'm able to buy about half the infrastructure, and use the rest on city states (I had 9 city states at Ally status by the end of my latest game).
I find that a few things are really key for a quick space victory. First, KILL (OR SEVERELY MAIM) YOUR NEIGHBORS! And do it early. There is basically NO chance that they aren't going to cause you trouble down the line if you don't. Either they get tired of you and declare war on you, or if they are too scared to fight you directly, then they will go on a rampage and kill every city state in sight, which is just as problematic. If it doesn't come down to war, you simply need the land anyways, and you won't be able to settle enough land on your own for a fast win (rex'ing hard in the beginning will undoubtedly cause them to declare on you anyways). In my second game, I went after Napoleon immediately since he's always a blood thirsty war monger, but left Lizzy alone. This was a mistake, because as soon as she hit longbows, she went and conquered 4 city states before I could muster up enough troops to shut her down. This cost me at least 10-15 turns off my victory time, maybe more.
Second, research agreements are important. Once you hit the start of your massive golden age and start raking in the dough, start making research agreements with EVERYONE. My second game (1870 AD win) should have ended much faster, but unfortunately Hiawatha had conquered EVERYONE on the other continent by then, and both Lizzy and Ghandi (on my continent) were too poor to ever make agreements with me. Some of the agreements would undoubtedly give me useless techs from the bottom of the tree, but I could have shaved off another 10+ turns at least if I had a few trading partners.
Third, great scientists are even more important. This is another area where I screwed up and it cost me a good number of turns in my second attempt. I only managed a total 6 great scientists. If I had planned it better I suspect I could have gotten about 8-10. Save these guys till the end, and use them to blow through the final part of the tech tree. First thing you do is get about 2-4 techs away from Rocketry, the pre-req for Apollo program (beeline it right after Steam Power and Railroad). Blow some scientists (and/or the final policy in the Rationalism tree, which gives two free techs) to get to it quickly, and start building it in your highest production city. Now start on the rest of the top of the tree. While you are building the Apollo Program, you can research another 3-4 techs. You are going to be about 12-14 away from the final spaceship part tech (Nanotechnology), so if you have a good number of GS's saved up and a get few lucky Research agreements, you can finish Nanotechnology within a few turns of the Apollo Program. By now you should have your production infrastructure in place, and should be able to finish off the spaceship parts in less than 30 turns.
That's about all I've got for now. I think Persia is the best candidate for quick space wins for all of the reasons above. Babylon may be good as well, but I don't have them so I can't test it out. If you do everything right, I think a pre-1800's win is very possible.
Feel free to add your own tips or other strategies, or to comment or ask questions about mine.