FreeCol

FreeCol is a turn-based strategy game based on the old game Colonization, and similar to Civilization. The objective of the game is to create an independent nation.
You start with only a few colonists defying the stormy seas in their search for new land. Will you guide them on the Colonization of a New World?

http://www.freecol.org/
http://sourceforge.net/projects/freecol/
License : GNU General Public License (GPL)
Operating System : All 32-bit MS Windows (95/98/NT/2000/XP), OS Independent (Written in an interpreted language), Linux
Programming Language : Java (Would require Java portablizer integration)