Required Tech: Monotheism
Effect: Can build Missionaries without Monastery, +25% for Buildings in Cities with State Religion
Use: Spreading Religions in any game type, speeding up production of buildings in Ironman/ffa and classi/medi teamers.
Organized Religion has three kind of uses. The first is in Ironman/ffa where its what you usually run longterm, when you were able to found a Religion. Missionaries can then be used to get the culture expansion to fatcross in newly founded cities, having a State Religion will give you one more everywhere and the production bonus is very useful, since you will build a lot of economy buildings. If you play a cottage economy, Organized Religion is what you usually run all the time, except for GP phases or war.
In classi and medi teamers Organized Religion in basically the only Religion Civic available all game being adopted with slavery and monarchy right at the start. (Theocracy possible in late medi, but often without effect). In those games you dont need a lot of building but only some, so it might be useful to adopt your religion or it might not be, depending on if you need the missionaries anyway for culture expansion or not (creative trait/good resource distribution).
In later era start game (reni upwards), you will likely pick Spiritual trait. In this case you can adopt Organized Religion for a few turns in the beginning to spread your religion before going Theocracy, which you will be running longterm for stronger units. If you are not Spiritual, its more efficient to build a Monastery in one city and adopt Theocracy right from the start. However note, that you can't build Monasteries in Modern/Future start games making Organized Religion the only way of spreading your Religion, which is one of the main reasons Spiritual becomes mandatory here.
Required Tech: Theology
Effect: +2 Experience Points for Units build in Cities with State Religion, Non-State Religions can not be spread
Use: Buildings stronger Units in any game type, when going to war.
Theocracy is pretty plain. In games where you fight and have it available you spread your Religion and adopt as long as you are building units, so the have one more Promotion (+3 EP from Barracks +2 from Theocracy). Running Theocracy is preferable to vassalage, because you will be sacrificing weaker Civics in the Religion branch. Since you are building units anyway the other Religion Civics don't help you much anyway, but Bureaucracy, Nationhood or Free Speech in late game are still very strong civics. In later era teamers Theocracy is the standard way of getting the second promotion on your units. In Ironman/ffa you wont always have a Religion and Theology might not be on your tech path so you may choose to rather run vassalage or not bother with the second promotion (e.g. because you might be fighting a very inferior opponent).
Required Tech: Philosophy
Effect: +100% Great People points in cities with State Religion, +1 Support Cost per Military Unit
Use: Speeding up Great People in any game type, either with running Pacifism longterm or with so called GP phases, where you switch to pacifism for a few turns, putting in massive Specialists during that time.
Pacifism can only be used longterm in peaceful Ironman/ffa games, because of the additional Unit Support cost, that are a too big backlash if you have to keep up a significant army. If you don't have to do so, running Pacifism makes a lot of sense, because it's a very strong Civic, especially when you don't have a Philosophical Leader. It will allow you to get a lot more Great People, providing you with a significant advantage. This is especially useful if you run some kind of specialist economy.
Another good way of using Pacifism are GP phases, including Caste System. You adopt those two civics for a few turns, putting in massive Specialists, often even starving you cities to use the Pacifism bonus as much as possible and then switch back to you original Civics after a few turns. This requires either Spiritual trait or a golden age, because the gain doesn´t justify two turns of anarchy.
Required Tech: Liberalism
Effect: No State Religion, +1 per Non-State Religion in a city, +10% in all cities
Use: Increasing happiness combined with spreading several Religions in ffa/Ironman when facing big problems there. Being run, when you dont have a Religion spread in ffa/Ironman.
Free Religion is actually i pretty useless Civic, that you only use, when left with no other options and only in Ironman/ffa at that. The +10% is actually only 5% most of the time, because its applied to your base commerce and you will be having about +100% already, from several science buildings at that point.
The only real use of Free Religion, is that you can solve massive happiness problems with several religions combined with Free Religion.
[B][U][SIZE="3"]A few final words[/SIZE][/U][/B]
Civics are one of the strongest single factors in your gameplay. They have a huge impact on your game, determining the outlet of your economy and also being a great factor in deciding on your tech path. While micromanagement of cities is very important too, it consists of thousands of small decisions, where a single mistake rarely makes a big difference. They only sum up.
With Civics on the other hand a single mistake can easily cost you the game, so be careful and take your time on deciding on which to adopt.
Also checking you opponents Civics in the foreign Advisor is a good means of determining what he is doing. E.g. when someone switches to Theocracy and Nationhood you should immediately be wary of being attacked.
[URL="http://apolyton.net/entry.php/17-Civics-in-Focus-I-Government-%28Civ4%29"]Part I: Government[/URL]
[URL="http://apolyton.net/entry.php/18-Civics-in-Focus-Part-II-Legal-%28Civ4%29"]Part II: Legal[/URL]
[URL="http://apolyton.net/entry.php/23-Civics-in-Focus-Part-III-Labor"]Part III: Labor[/URL]
[URL="http://apolyton.net/entry.php/29-Civics-in-Focus-Part-IV-Economy"]Part IV: Economy[/URL]