Domination in 1864 AD.
I entered MA at 50 BC and immediately switched government to Feudalism. The Republic would been perfect because I didn't have many units anyway, but unfortunately no one researched it until 550 AD.
A small force was sent to Russia and China to grab as much land as possible between 350 AD and 460 AD. I captured 2 cities, then made peace and got 2 cities far from my land.
A suicide galley was sent west 600 AD and survived. I got contact with Hittites, Arabs, Sumeria and finally Ottomans. The Ottomans were the most advanced and they traded 890 gold for one of my techs. That allowed me to research at 100% rate. Still, I was far ahead of everyone and simply ran away.
At 820 AD, Navigation was discovered, and I traded maps with everyone and found that Korea had wine. They were the most backward civ, so I waged war against them with about 8 + 2 samurais. Golden age was triggered 830 AD, and I used that time to improve my cities and conquer Korea. No great leader appeared in this war.
Kyoto eventually became a science beast with Colossus, Copernicus Observatory and Newton's University. I could discover something new every 4 turn without losing gold for a long time because of this. Around 1200 AD Kyoto had something like 240 science/turn. Later with SETI and other improvements, here is what Kyoto looks like:
Science progress:
War against Russia
When gunpowder was discovered 980 AD, I noticed that I had no salpeter. A russian town was sitting next to one so I prepared for a big fight against Russia and finally declared war in 1370 AD. With Americans on my side, Russia was destroyed 1560 AD. America looked surprisingly strong with about 10 knights and 20 crusaders running through a city.
One great leader appeared in this war which I used to hurry a small wonder.
War against China
Around 1700 AD, I had tens of tanks and plenty of well developed cities that would re-enforce them and thought I would cut through China easily, so I waged war, simply because I wanted more land. China had riders and put up a fight, but the war ended in my favor 1754 AD. One great leader appeared, and I used it for an army of tanks.
War against America
With all those tanks hanging around, I wanted to take advantage of them. War was declared against America in 1772 AD It was messy at first, but eventually I ran over America with cavalry, tanks, artillery and bombers. America was destroyed 1808 AD. Four great leaders appeared in this war thanks to Heroic Epic and the double attack ability that tanks have. I used them to rush factories and to build another army. Three continents were now in Japanese control.
War against Hittites
America had not fallen, but it was close enough, so I sent about 10 tanks to Hittites and declared war 1796 AD. They had luxuries that I wanted (dyes and ivory) and they could only defend their cities with pikemen and longbowmen. They put up a big fight though. I lost maybe half of my tanks and had to send re-enforcement's. The Hittites were destroyed 1832 AD. One or two great leaders appeared in this war, but at this point it didn't matter much.
War against Sumeria
I had almost completed my collection of luxuries, and needed only gems and incense. Gems could be obtained from a colony (although not for long), but the incense required trading or grabbing it from Sumeria or Ottomans. Sumeria was a little backwards, but they had riflemen, but that was nothing against tanks and bombers so I declared war 1860 AD. After grabbing 3 of their cities, I had completed a Domination victory in 1864 AD.