Civ 1:
Rome, Russia, Babylon, Zulu, Japan, Germany, France, Egypt, Aztecs, USA, China, Greek, England, India, Mongolia

Civ 2:
As above + Celts, Vikings, Spaniards, Persians, Carthage, Sioux

Civ 3:
America, Arab, Austria, Aztec, Babylon, Byzantium, Carthage, Celts, China, Netherland, Egypt, England, France, Germany, Greek, Hittites, Inca, Indian, Iroquois, Japan, Korea, Mayans, Mongolia, Ottomans, Persia, Portugal, Rome, Russia, Spain, Sumer, Vikings, Zulus

Civ 4:
As above + Ethiopia, HRE, Khmer, Mali, "Native American" (no Iroquois)

Civ 5:
Same as Civ 3 + Assyria, Brazil, Denmark, Ethiopia, Huns, Indonesia, Morocco, Polan, Polynesia, Shoshone, Siam, Songhai, Sweden, Venice

Civ 6:
Same as Civ 3 + Australia, Brazil, Canada, Cree, Ethiopia, Georgia, Gran Columbian, Hungary, Indonesia, Khmer, Kongolese, Macedonia, Mali, Maori, Mapuche, Norway, Nubia, Scotlan, Scythia, Sweden, Vietnam