Happiness
Keeping your population happy has always been a feature in Civilization games, but it takes a turn here. In early games it was more of a city by city issue. A given city might have a happiness issue, but it didn’t affect other cities that much. And a common strategy in early versions of Civ was to pump out settlers and build as many cities as you possibly could. In Civ V that strategy has been decisively nerfed due to the Happiness mechanic.
To begin, you can see your happiness level at the top of the screen. There is a smiley face icon with a number next to it, which represents you current level of happiness. As long as the level is zero or greater (i.e. positive happiness), the icon will be the usual yellow smiley face. In this condition, your empire grows as normal, and each turn the Happiness number is added to the Golden Age counter, which is also visible at the top of the screen. Accumulate enough points on that counter, and you enter a Golden Age, with bonuses. But if the Happiness level falls below zero, your empire is Unhappy. In this state your production falls by 2% for every point below zero, and your gold revenue falls by 2% for every point below zero. Also, your units have reduced combat strength that falls 2% for every point below zero. Finally, your food accumulation (which feeds growth) falls by 75%.
If it falls to -10, it gets worse. You are now Very Unhappy, and population growth stops completely, and you can no longer train new Settlers. In addition, rebellions break out in the form of “Barbarians” suddenly appearing in the middle of your territory who will have the most advanced units your technology allows. Meanwhile, the reductions in Production, Gold Revenue, and Combat Strength continue. If, for some reason, you let it go until you hit -20, some of your cities, particularly border cities may revolt and join another Empire.
This does not mean that falling to a -1 or -2 for a few turns is all that serious. But what you need to watch out for is the gradual decline over many turns. You should be paying attention to the Happiness level at all times, and plan to take actions to deal with it. If you want to know more about the factors that affect your Happiness level at any given time, just mouseover the Happiness icon and a pop-up window will give you details. You will see that some things add Happiness, and other things produce Unhappiness, and the the Happiness level you see is the net of those two.
The things that add Happiness begin with Luxury resources. Chances are you will have access to one or two near your first city. Getting those resources developed (through a mine, plantation, etc.) and working them with a citizen will add Happiness to your Empire. Now only the first copy of the resource adds Happiness, but if you have a second copy, you can develop that and use it in trade with another Empire to get a copy of one of their luxury resources. So right from the very early stages of settling your first city, you should be on the lookout for Luxury resources you can develop. Building relationships with the independent City-States can also bring you Luxury resources that they have. There are many other sources of Happiness. Every Natural Wonder you discover adds to Happiness throughout your Empire, so exploration is important. For this reason, you will find that most experienced Civ players will make training a Scout to explore (sometimes 2!) their very first production in their first city. Finding Natural Wonders is not the only reason to do this, of course; learning more about the terrain and finding good places for another city, and searching out Goody Huts (i.e. Ancient Ruins) are other good reasons, but it does make sense. Some buildings add to Happiness, as do some Wonders. And there are Social Policies and Religious Beliefs that can add to Happiness (or equivalently, remove Unhappiness).
But when we look at the causes of Unhappiness, two things stand out, particularly in the early game. The first is how many cities you have, and the second is your population level. Growing too fast, too soon can kill you in this game. This explains why when we looked at Citizen Management there was an option to stop City growth in a city. If that would push you into a negative Happiness level it might be better to stop the growth temporarily, maybe build a Circus or something to increase Happiness, then let growth continue. And it also explains why you might be better off not going the Liberty policy tree route, at least early on, because it is designed to make you grow faster.
For a beginning player, I would suggest the objective for the early game, say up to turn 120 or so, would be to have 4 good cities, build a Library in each of them, and then build the National College. Note that the National College requires you to have a Library in each city before you can build it. And indeed most National Wonders work similarly, which means that if you keep building more cities you may never get to those National Wonders until very late, and you will miss out on the benefits they give. The National College, for instance, gives a 50% boost to the science output of the city that builds it, and adds 3 Science and 1 Culture to the output of the city. If you get that 50% boost early on in the game, it can propel your Science throughout the game. If you don’t get it until the Industrial or Modern eras, you have given up a lot.
Generally by the time you get to turn 350 or so Happiness is not likely to be a problem simply because you will have done enough things to add Happiness. I find in my games that by this point I may be comfortably in the 20-30 range. But in the early game it matters a lot.
Eras
We mentioned Eras above, and they are another key concept. Eras unlock new policy trees, but they also unlock the World Council and the United Nations in complicated ways. And starting with the Renaissance Era, you get a new spy every time you enter new Era. So these are some of the ways Eras can matter in the game. The Eras are:
- Ancient
- Classical
- Medieval
- Renaissance
- Industrial
- Modern
- Atomic
- Information
In the game, these Eras are defined by the technologies you have researched. And to be clear, different Empires can be in different Eras at the same time. The game will notify you when another Empire has moved into a new Era. To see how this works, open the Technology Tree by clicking the Science icon on the upper left, and you will see that the tree is divided into sections named along the top header. You move from one era to the next when you either 1) Research all of the technologies from the previous Era; or 2) Research your first technolgy from the next Era. From this, you can see that you can advance through Eras pretty quickly by skipping over Technologies. I’m not saying you should, necessarily, but the game does allow it, and it might make sense in some circumstances. For instance, if you want a Science victory, you will want to unlock the Rationalism policy tree ASAP, so rushing into the Renaissance Era would make a great deal of sense, and then you can go back and pick up the ones you skipped. And given the way the techs tie together as prerequisites, you will end up having to do it at some point anyway. And another benefit to rushing Eras is that the techs from the earlier era become cheaper to research when you have move up an Era. It is a kind of micromanaging to do all of this, but it is an available strategy.