FreeCiv is a free and open source empire-building strategy game inspired by the history of human civilization. FreeCiv.net is a fork of the original project, designed to run in a web browser. The game can be played online against other players, or in single player mode against AI opponents. The game uses the HTML 5 canvas element to render the isometric map.
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The idea of creating a version for Freeciv which would be playable online in a browser came about some time in 2007, and this project has evolved into what it is now since then.