Originally Posted by Nerevarine
I want to avoid talking about whether one series is "better" than the other or not - I enjoy both series for different reasons, and playing Civ way back when introduced me to PC gaming, ensuring that it will always have a soft spot in my heart - but I will point out what I personally see as major differences between the two series.
In terms of "historical flavor," The Civ series has always felt more like "fantasy" for me. For starters, having immortal, god-like leaders that never age or have successors, the technology "race" throughout time that never allows a player to get immersed in a particular era, basic diplomacy, resource-collection driven economy, random factions like the Indian Nations acquiring advanced technologies that aren't aligned with their culture, etc.
I would never want a strategy game to adhere to "real" history too much - the fun in these games is the idea of alternate, dynamic events taking place within "realistic" contexts - but EU is much more "grounded" in comparison. Neither approach is necessarily better, they are just different.
I wouldn't consider EU to be a "4x" game like Civ, as it's missing some "X" elements - such as exploration. You don't need to scour the land for resources, build new cities (one element of "expand") wherever you feel like, manage worker units, etc. Part of how EU differs from 4x gameplay is that it is extremely diplomacy-driven, and failing to navigate this gameplay aspect gracefully will lead to consequences. In Civ, it doesn't really matter how poorly one handles diplomacy in most cases, so long as the player has the military to run roughshod over every faction. Declaring war is often trivial, alliances and trade do not have a big impact on gameplay, and the focus of Civ lies mostly in building cities, exploring unknown regions of the map, researching technology, and exterminating the enemy with military pursuits.
EU is focused much more heavily on diplomacy and economy; military engagements cannot run properly without these two elements running smoothly. In comparison, Civ possesses a very simple approach, almost "arcade-y" for a strategy game. This isn't necessarily a bad thing however; being able to jump right into the game with little learning curve establishes a nice, fluid rhythm, and is quite nice depending on the player's mood.
So those are some of the major differences that I see between the two games, and it reveals vastly different experiences in my mind. While Civ is focused on traditional 4x elements and is relatively simple in an almost "arcade" way, EU is heavily focused on diplomacy and economy. They are both great series, but for different reasons. Civ is there for an addictive, "just one more turn" style that relies on rhythm and constant forward progression in the classic 4x style. EU is more of a slow-burn, requiring the player to always think several steps ahead when planning the next move.