FreeCiv - Freeciv is an open-source, turn-based strategy game based on Civilization II.
The Battle for Wesnoth - The Battle for Wesnoth is a turn-based tactical strategy game with a high fantasy theme.
Freeciv for Android - Port of Freeciv to Android - similar to Civilization series.
Widelands - Widelands is a free, open source real-time strategy game with singleplayer campaigns and a...
Sid Meier’s Civilization VI - Sid Meier’s Civilization VI is a Turn-based Strategy, War, Tactical, Single and Multiplayer video game created by Firaxis and published by 2K.
C-evo - C-evo is a freeware empire building game for Windows