France: Human player always controls the French, which always get owned by every sort of military, including barbarians and mere warriors, and occasionally roaming workers. French military have the special ability to surrender to everyone like non-combat units, including themselves, immigration, culture expansion. Every kind of industry will refuse to work because there's city unhappiness "We strike against everything!", yet they produce their finest material, White Flag. Also, France and Germany always start close to each other. That close...
The USA: It keeps referring the USA as "the World" in every circumstance. Other Civs will be labeled equally as "Rest of World". US Military units will defeat everyone and everyone that get across their way, except in jungles, and lately, in deserts. Has an itch for invading countries that are distant from its homecountry. Also, USA cities have negative culture value.
Germany: German civ always shares boundaries with France, which is German citizens' main source of happiness and fun, and main vacation place for German military. In times of war, everyone hates Germany.
Italy: In the Italian civ a change of goverment happens every turn. People blame the government for everything - more specifically, whenever something usual happens, i.e. weather change, government collapsing, or France getting owned, while they don't care if their civ has not a proper military, a proper industry, proper lines of transportation. It manages in some way to be a - somewhat - Great Power in the late period of the game, but no one cares. Italy will also join the - supposed- winning side in a war, and swaps sides quite frequently, but luckily for her no one cares. All other civs behave as usual.
Poland: Everyone forgets about Poland, Germany finds it accidentally in 1939, then everyone forgets, then Russia finds it accidentally in 1945, then it's left into oblivion for the rest of time.
Russia: The Russian civ controls 50% of world space, the USA control the other 50, every other civ is vassal of the former or of the latter. Occasionally, a war would start...
Also, the Russian leader is really immortal. Whenever one leader dies, they just hibernate him, appoint another leader and claim that the first one is still alive from the dawn of humankind.