New personal record in 1000 AD (Vanilla): I unlocked the Byzantines and the Vikings from MinorCivs to Playable, and it was amazing. The Byzantines dominate because of their troop level and central position. I also changed the diplomatic structure to:
Vikings v France, England, Holy Rome
Arabia v France, England, Holy Rome, Spain, Byzantium, Russia, India
Byzantium v Holy Rome
China v Mongolia
I then added the Permanent Alliance and Aggressive AI options, and played as the Byzantines.
Saladin started strong, holding onto Cordoba and taking Ujjain from India. I managed to take Syracuse from Holy Rome, then followed that up with Jerusalem, Mecca, and Cairo. Spain took Cordoba, while Peter began to aggressively settle Russia, eventually colliding with Mongolia. Leftover troops took Rome and Baghdad, and the Vikings managed an amphibious invasion, taking Aachen (changed the Roman capital, moved it 1 NW). Holy Rome was dead. I sped up and starting taking European cities, finally taking out Cordoba in the 1600s. With a European production base, I managed to finish off Saladin and India. Then I just settled down for a Space Race VIctory.
Fun.