Emperor - Marathon - Continents - (normal size normal settings)
The following should get you safely to the late Middle Ages, assuming you can get your hands on Copper.
Stage One
Found = Capital city
Tech = Bronze working, (adopt Slavery), then bee line Masonry
Found = City 2 (chop and whip the settler from your Capital)
Wonder = Great Wall (build and chop it)
Tech = research a health tech and a happiness tech if there is a luxury nearby, so as to allow cites to grow to size 5+ and don't forget to research / build villages as fast as you can.
Found City = 3 (beware economic meltdown as 3 cities is really pushing it)
Great Person = Great Spy guaranteed to pop out, (settle him in your capital).
Religion = adopt the most popular one
N/B: You may be at war during above stage, should a nearby rival have rushed you, (usually Monty or Shaka), so switch research to Hunting to get spermam if that happens, or is in danger if happening. You now have Axeman + Spearman and can build/chop/whip walls, which should make your 3 cities reasonably safe.
Stage Two
Tech = Bee line to get spys
Unit = build/whip/chop a Spy and send to highest tech civ, but leave him to zzzzzz in the rivals city for circa 5 turns, (it massively reduces the cost of stealing technology)
Tech = Bee Line to get Great Library
Great Person = Great Spy again, (send him to settle in the rival civ with the highest tech).
Wonder = Great Library (build/chop)
N/B: You may lose your one spy, so build/whip 2 more as soon as you can and send them off to zzzzz as well. You must have them wait in the rivals city, as you will steal twice as much technology just for waiting a few turns. If you are at war, then steal a quick technology and buy off the warmonger so that you can be at peace.
The rest is up to you, but assuming you trade Alphabet / Writing when you research them for the early techs you missed, then your 1 - 3 spys will now be able to steal circa 6+ technologies for you, and your capital will pop out another Great Spy whilst that is happening, who can also be sent off to settle in the enemy civ. This third Great Spy will give you the same amount of spy points as the first, (think it's 9,000), but the more advanced the tech, the higher the cost, so your third Great Spy is probably only worth circa 3+ techs.
The Great Library itself will add 2 scientists to your Capital, so your Capital is now more likely to produce Great Scientists once it's built, rather than Great Spys. Needless to say you could tweak your capital by building a Courthouse and then temporarily adding another Great Spy, or you could settle two Great Spy in your capital rather than just one, so as to increase the chances of it producing yet more of them, but stealing technolgy runs out of steam by the late middle ages on Emperor level, as the costs just become to great.
So, with the Great Library safely under your belt, you can now temporarily zero all science research and assuming you will be stealing or trading to get Monarchy and Currency, then you can now expand like a madman, yet still stay close to the tech leader. With the Great Library built, your target should be to whip settlers / military to create or conquer circa 6 more cities ASAP. If you have to conquer a few cities from a lower tech rival who has settled them close to you, then you now have the tech lead to do it. N/B: The capital city of all rival civs is situated in as good a spot as your capital, so always try and capture the enemy capital before they vassal to some other civ, (happens all the time on Emperor - really annoying).
Needless to say, try to build / conquer in a circle, with your capital at the centre, or so that your capital is as far away from the front line as possible, because you can't afford to lose the improvements you have built around your capital. Be aware that all coastal cities are very vulnerable to naval invasion on Emperor level, and should have as strong a garison as you can afford.
Once you have established your core cites, then consolidate your position, and push that science slider back up. The tech leader will now be researching faster than you can steal, so use the usual technique of following just one technology tree and trading tech with everyone you can.
You will now be leaving the middle ages, you will have a reasonable sized civ, and although not number 1 in tech, you will be in a strong tech position.
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Late game on Emperor
If you are aiming for a Space Victory, then be aware there is a strong chance on Emperor level that the top civs will achieve a Cultural victory, just as you are building your spaceship, so you MUST keep an eye on the cultural state of their top 3 cities. If you are faced with this problem late game, then your only solution is a lightening raid targeted at the 3 problem cities. You may have to raid between 1 - 3 civs to stop them from each gaining a Cultural victory, so plan surgical attacks on the culture cities, rather than an all out war of conquest against each of the civs.
Regards - Mr P
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