I've had some ideas. I love the peaceful victories, so these civilizations focus on those.
Furthermore, most of them are modern civilizations, having more modern leaders and uniques.
VATICAN CITY (or The Holy See)
Pope Paul V (Latin or Italian)
5 first cities: Vatican City, Prague, Danzig, Vienna, Augsburg.
White & yellow.
Start bias: none
UA - Gains faith for each city following The Holy See's religion. Can buy units with faith.
UU - Swiss Guard. Replaces Swordsman. Increased strength. Gains faith for each unit killed.
UB - St. Peter's Basilica. Replaces National Epic. +1 Spot for Great Work of Art. +2 Tourism for each World Wonder.
The smallest country in the world, and one of the most influential too. Having it work as the Holy Roman Empire, I think it would be very interesting to play an almost purely religious game.
Obvious choices for victory would be cultural, but domination would be possible too.
TOGO
Edem Kodjo (French or Ewe)
5 first cities: Lomé, Sokodé, Kara, Palimé, Atakpamé
Green & brown.
Start bias: Plains.
UA - Each Togolese city adjacent to a river will provide one of two unique luxury resources (coffee, cocoa).
UB - Fetish Market. Replaces Market. +1 Tourism and +2 Gold.
UB - Takienta. Replaces Monument. +2 Culture and +1 Happiness.
One of the more modern ideas. One of the fastest developing countries today, and an interesting one. A Takienta is a famous Togolese mud house, and the Fetish Market is basically a voodoo market.
With coffee and cocoa being the main export, and thereby getting those as luxury resources, and having the Fetish Market and Takienta, Togo could go for diplomatic or cultural victory.
GREENLAND
Kuupik Kleist (Greenlandic)
5 first cities: Nuuk, Sisimiut, Ilulissat, Qaqortoq, Aasiaat
White & dark grey
Start bias: tundra/snow
UA - Gains +1 Food and +1 Culture for each snow or ice tile within Greenlands borders.
UU - Inuit Fishing Boat. Replaces Fishing Boat. Gives +2 Food and +2 Culture on worked Fish and Whales.
UU - Sirius. Replaces Cavalry. Increased strength, movement and sight. Gains combat boost in tundra and snow.
Because, it would be awesome to play a game as Greenland. Greenland is famous for fishing, and so the Inuit Fishing Boat is explained. Denmark has a part of their military on Greenland, a dog sled patrol, those known as the Sirius Patrol.
Suited for cultural victory.
FINLAND
Carl Erik Mannerheim (Finnish)
5 first cities: Helsinki, Tampere, Oulu, Turku, Kuopio
Dark blue and grey
Start bias: tundra
UA - Cities improves Science with a percentage equal to the amount of citizens (to a maximum of 30%).
UU - Guards Sharpshooter. Replaces Musketman. Increased strength. Gives 25 influence when gifted to a City-State.
UB - Kansallismuseo. Replaces Museum. +3 Science. +33% Science.
Too few scientific civilizations, in my opinion. Finland's technological impact on the rest of the world, had it being a scientific civilization. Kansellismuseo is basically a national museum.
Scientific victory is the obvious one, but with the unit, diplomatic could be possible as well.
SCANIA (or Trelleborg)
Prince Valdemar (Danish or Swedish)
5 first cities: Trelleborg, Slagelse, Fyrkat, Nonnebakken, Aggersborg
Purple and blue.
Start bias: tundra
UA - +25% generation of Great Merchants. Receives a Great Merchant when unlocking a new branch on the Social Policy tree.
UU - Knarr. Replaces Galleass. Increased movement and sight.
UB - Ring Castle. Replaces Castle. +10% generation of Great Merchants in this city. +5 extra strength and +10 extra HP.
Let's agree, the current vikings (Denmark) isn't that impressive. Situationally good, but still not impressive. So that's where we have Scania/Trelleborg. Famous for being good merchants and a northern trading center, the ring castles (trelleborgar) are still a huge attraction today. A knarr is a viking ship meant to be used on sea.
Suited for diplomatic victory, but is probably well balanced for any victory.
MALI
Musa I of Mali (Malinké)
5 first cities: Niani, Ghana, Zaga, Manden, Zagun
Light brown and dark brown
Start bias: desert
UA - Founded cities on or adjacent to desert tiles have a 33% chance of allowing an extra trade route.
UU - Mandekalu horseman. Replaces Horseman. Increased strength. +10% combat strength if bought with faith.
UU - Mandekalu infantry. Replaces Composite bowman. Decreased range. Permanently -10% combat strength to any unit wounded by Mandekalu infantry (does not stack).
More African civilizations. The Mali Empire had great impact on African culture and economy, along with being good tradesmen. The Mandekalu horseman were often very important men (royal people, for instance) with impressive weapons. The Mandekalu infantry had crappy arrows, and so used poison to make up for that (explaining the -10 combat strength).
Suited for diplomatic or domination victory.
KAZAKHSTAN
Nursultan Nazabayev (Kazakh)
5 first cities: Astana, Almaty, Shymkent, Karaganda, Aktobe
Turqoise and yellow
Start bias: none
UA - Can purchase Great Persons with Gold. A Great Architect appears upon researching Engineering.
UU - Great Architect. Replaces Great Engineer. +100% Production to all cities within 10 tiles. Lasts 8 turns.
UB - Wooden Mosque. Replaces Temple. +2 extra Faith, +1 Culture and +1 spot for Great Architect.
Another modern civilization, this one focussing on Kazakhstan's cool architecture and wooden churches.
A pretty balanced civilization.
MALTA
Agatha Barbara (Maltese)
5 first cities: Valletta, Città Pinto, Città Hompesch, Cittá Rohan, Città Beland
Dark red and dark blue
Start bias: none
UA - Gains +5 Tourism for each island completely within Malta's borders. +15% combat strength on islands.
UU - 100-Ton Gun. Replaces Cannon. Decreased range and movement, but slightly increased strength. No bonus for attacking cities. When killing an enemy unit, has a 10% chance of adding a random artifact to the nearest free spot. If no spot is available, turns this artifact into 100 culture.
UB - War museum. Replaces Museum. Increased theming bonus for artifacts. +2 extra Culture.
Because, I love the ideas of more modern civilizations. While that UA would be great for any island nation, I think it's good for Malta. The 100-Ton Gun is one of the things Malta is most famous for, as they have one of only two in the world, of those impressive weapons. They're also famous for their impressive collections or war museums.
Suited for cultural.
SCANDANAVIA (or North Sea Empire)
Cnut the Great (Danish)
5 first cities: Wessex, Jutland, Mercia, Agder, Sjaelland
Dark green and light blue
Start bias: plains
UA - Allied city-states has a small chance of joining Scandanavia each round. Higher influence gives a higher chance (influence divided by 40).
UU - Halberdier. Replaces Longswordsman. +15% combat bonus against capitals. Small increased strength.
UB - Turf house. Replaces Granary. +2 food from each source of Sheep. +1 extra food. +5% extra food.
More vikings? Yep. I simply love vikings, and the North Sea Empire would make an awesome civilization. Halberds were used by the vikings, and the turf house is a building with way better isolation compared to the ordinary longhouses.
Best suited for a domination victory, probably. Could work for diplomatic too, but the UA would just remove delegates (which is a good counter to diplomatic victories).
LITHUANIA
Vytautas the Great (Ruthenian or Lithuanian)
5 first cities: Vilnius, Trakai, Brest, Minsk, Kernave
Light orange and light purple
Start bias: none
UA - +15% faster border growth in all cities. May purchase tiles 4 tiles away from cities.
UU - Moldavian plăieşi. Replaces Pikeman. +12% combat bonus when within 2 tiles of a mountain.
UB - Trakai Island Castle. Replaces Ironworks. Must be built on a single-tile island. +18 extra production, +8 extra strength and +10 extra HP.
The Grand Duchy of Luthuania controlled a huge part of Europe, and yet seems to be considered one of the more insignificant empires in history. I, however, think they deserve a civilization. They expanded very rapidly, and that's what their UA represents here. The plaiesi were peasants, working as border controls and ambushers in the mountains. The Trakai Island Castle is an impressive castle, located on an island in a lake, therefore the requirement.
Probably good for domination, but could work with any victory.
TUPI
Araribóia (Tupian)
5 first cities: Tupiniquim, Tupinambá, Potiguara, Tabajara, Caetés
Dark brown and white
Start bias: jungle
UA - Friendly units heals 25% when killing an enemy unit. Can turn 25% of a cities production into food.
UU - Caeté warrior. Replaces Warrior. Ignores terrain cost. -5% combat bonus against ranged units.
UI - Peanut farm. Can only be built on jungle tiles. +2 food, +1 unique luxury resource (peanuts).
A South American people, known for being cannibals, this explaining their UA. They grew lots of peanuts, and so the UI is explained.
Probably best suited for a scientific victory, but could go anywhere.
NEVADA
Isaac Roop (English)
5 first cities: Las Vegas, Henderson, Reno, Sparks, Carson City
Light brown and light green
Start bias: desert
UA - +2 production and +1 culture from mines. Starts the game in a golden age.
UU - Volunteers. Replaces Great War Infantry. Increased strength. 15% combat bonus if within friendly territory.
UB - Water Supply. Replaces Hydro Plant. 1 maintenance cost instead of 3. City does not have to border a river. +1 food to tiles bordering a river.
Partially based on the old west, but like Brazil, heavily focussed on the late-game. Volunteers made up much of Nevada's army during the civil war.
Probably well balanced.