I have played this game and it is very similar in regards to the military aspect of Civilization. There is no building cities, city improvements, or terrain improvements.
There are only 4 kinds of terrain- sea, plains, forest, and mountains. It is turned based. There is terrain marked with an "L" where if you move a unit on it, a new castle is founded for you.
You start of with a single castle in which you build military units which have different turn costs to build, and different movement rates, and attack and defense strengths. Some have bombardment ranges (Catapults, Balista), and some can transport other units (Horses, Ships). The goal is to capture your rivals' castles. It does play a lot like Civilization, but as far as I know there is no connection.