Z-Man Games has announced that an expansion for Christian Marcussen’s Clash of Cultures board game will be released in 2014.  The expansion, Clash of Cultures--Civilizations, will add 14 different civilizations to the game, which recaps the development and contours of the civilizations that stretch across World History from Stone Age settlements to the invention of gunpowder (see "'Clash of Cultures' Board Game").  Each of the 14 new civilizations will have its own unique advances and different leaders. 
There will also be a few new City pieces that players will be able to use to increase the size of their cities, but it is important to remember that a player can only place four pieces around his or her settlements, so it is crucial to choose those pieces very wisely.
The Civilizations Expansion will also add "Elephants" and "Horses" to the game.  Since not all civilizations had access to horses or elephants, not all of the civilizations in the game will have access to them either.  Further details concerning the Clash of Cultures--Civilizations Expansion will be released in the coming months.