In Freeciv you have to take into consideration terrain, resources, cities, economy, units, combat, diplomacy, governments, technology, wonders and many other things both for your and all competing civilizations.
Freeciv is designed as an open source version of Civ 2, which is quite an old game at this point. This means that many of the mechanics now found in the more modern Civ releases are not to be found here. It also means the graphics are quite dated looking.