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?

Minimum system requirements: 

A Java Runtime Environment >= 1.5, A display >= 1024x768