Happiness in Brunelleschi represents the welfare and satisfaction of the people living in your Settlement. There are 6 types of Happiness in each Settlement and district, representing the six primary ways a ruler can provide for their population's needs. If any of these Happiness types are unbalanced, it can represent a lack of balance in your city planning. The Happiness types include Security, Health, Prosperity, Faith, Education and Respect.
Consequences
Why bother to maintain the Happiness ratings? After all, it's not like your population has real feelings.
Unfortunately for the unfeeling tyrant, the NPC populace is not completely helpless. If their living conditions become intolerable (a Happiness falls too low), they will trigger a number of unpleasant Scenarios. Combining low Happiness with an oppressive government may even trigger a Revolution in which the NPCs try to overthrow your callous rule and make a change to the Civic Systems of the settlement.
Happiness triggered Scenarios are not always negative. Incredibly successful Sovereigns can trigger positive scenarios. In these cases, the people will, somehow without stopping their work-production, throw a huge party in celebration of how happy they are. During these scenarios, the settlement benefits from additional Bonuses, and even more benefit is gained if the scenarios are successfully completed by the player-residents.
Happiness from Buildings
The main way for Sovereigns and Ministers to raise their Happiness ratings is to build Happiness-providing buildings. Most buildings provide some passive happiness effects, not always good. Main buildings and high-rank buildings often have powerful happiness bonuses on top of their primary function. Some buildings provide nothing but Happiness bonuses and can be built strategically to balance/enhance your settlement's overall satisfaction. Many buildings provide a positive effect to one Happiness and a negative effect to another. Happiness focused buildings often will provide a local (district) bonus and a small but broader settlement bonus to the same Happiness type.
Each of the NPC population types require (use up) a certain amount of each Happiness type in the district they live in. Children, the Sick and the Elderly also take up Happiness based on their state. This means that housing-focused districts will need to save a few lots for Happiness buildings to maintain the satisfaction of their populace. Churches, Guardhouses, Post Offices, and Libraries will become common in residential areas in order to maintain local Happiness.
Resident Exemplars also require Happiness maintenance. Most cost about as much happiness as a Peer NPC, with the exception of homeless exemplars. Homeless player-residents are assumed to be roving the streets causing trouble. It frightens and discomforts or NPCs to see a powerful member of their society acting like a vagabond and Happiness drops more quickly with each un-housed player. It is to the benefit of rulers to either provide player housing or seriously buff-up their Happiness infrastructure.
Happiness-Effecting Events
Scenarios and other various events can temporarily effect your district/settlement Happiness ratings. District and settlement-wide effects can be beneficial, but also dangerous. Any temporary negative Happiness effect can tip an ill-maintained settlement over the edge into an Unhappiness Scenario. These temporary effects are often from randomly triggered scenarios and are not anyone's fault. Still, rulers are advised to maintain a safe Happiness margin to prevent these surprises from becoming disasters.
Many actions, especially those gained at the higher levels, provide Happiness bonuses. Rulers who find themselves in a tight spot and need an immediate (if temporary) balm on Happiness should seek players who can perform these actions. In many cases, a high-level exemplars may need to be paid to spend the action points and material cost of the action.
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Happiness Types
Security represents how safe it is to walk the streets of your Settlement. The higher local Security, the more likely criminal acts will be detected and criminals will be caught for trial. Security is not how safe your districts are from attack, that is a Defense rating. Defense buildings usually also improve settlement/district Security on top of raising the local Defense rating.
Internal Security buildings can be built throughout a Settlement to improve local Security ratings. These add an invisible police-force reinforced by local Garrisons and Exemplars on patrol. Performing illegal actions in a settlement/district with high security seriously increases the chances of getting caught. Likewise an area with tragically low Security may be rife with crime and characters seeking illegal skills will gather there. Commander characters will earn actions that can temporarily raise local Security.
A population that feels very secure is grateful for the local police force and is likely to throw a Parade scenario for the settlement. NPCs in a settlement with dangerously low Security will begin to resemble their environment and become hooligans. When the Security reaches a critical low, the people will lose all sense of lawful conduct and break out into a Riot. Completing the Riot scenario will only temporarily appease your unruly people. You'll still have to improve Security to prevent another Riot from occurring.
Health represents how much of a health-hazard your settlement/district poses to the population within. Do the streets run with sewage? Is the air filled with dangerous smelting and tanning fumes? Allowing your Health to become too low has dire consequences for your population. Members of the active work-force will become sick and leave their jobs. The women of your settlement will become too ill to conceive and fewer children will be born. Workers will become elderly and then die faster.
Increasing your settlement and district Health ratings can be done with several kinds of buildings. Water-treatment and distribution buildings are powerful Health sources, while those dedicated to naturalistic living and safe food production also tend to provide local Health bonuses. Nobles and Clergy characters will be able to influence Health more so than their comrades.
A Healthy population will have fewer Sick, have babies faster, have longer lives and have a few valued elderly. Populations that experience near-perfect health are aware of how difficult this is to achieve for their rulers. They are swept up in manic joy and gratitude and throw an impromptu Carnival "while they have their health" so to speak. Settlements that suffer profound unhealthiness will not revolt, the people are too unwell to fight. In this weakened state, any small illness can become a Plague scenario in your Settlement, causing all production to be cut in half while your work-force dies of illness in their homes and your refuse-filled streets.
Faith doesn't describe any particular religion but the People's need to gather and worship something. Even if your National Religion is Atheist, your populace will gather in Faith buildings and discuss how there is nothing and their responsibilities as godless beings. Faith is the people's sense of community and spiritual morale. Faithful people who see a moral atrocity committed are more likely to report it. Low Faith will cause the people to become fearful, unable to know their place in the world and what the future holds for them. The people will become petty and superstitious with no shared beliefs to bind them as a community.
Monuments and shrines alike, there have been many structures built in praise throughout the ancient lands of Renaissance Europe. While most centralized worship resembles Christianity in this time, travel was common and the old faiths are by no means dead. From the Chapel to the Basilica, these buildings are dedicated to raising local Faith, whatever flavor it may be. Clergy characters can learn several actions that can temporarily raise the Faith of their surroundings.
Faith is a vital part of the lives of your working populace. In order to see a greater meaning in their work and maintain a healthy sense of community, they need to have a faith in common. When Faith is high, they feel exalted in their purpose and brought together by a communal spirit. This can trigger a free Holiday scenario. If worship simply cannot be achieved (very low Faith), the people may become convinced your settlement is Cursed, causing them to stop trusting their Ministers until the scenario is resolved.
Prosperity represents how happy your people are with the industry in your settlement. Are coins passing through their hands? Are they constantly processing and distributing goods? If so, then Prosperity should be adequate. When the people are happy with their materials, they will build and upgrade more efficiently. Some Settlements will have naturally high Prosperity based on which buildings are preferred by the leaders. Other settlements may constantly struggle because their economy isn't based on wide-spread production and commerce. Trader characters are gifted at raising Prosperity and several of their actions can provide this temporary benefit.
The Renaissance world is flowing with rich and diverse commerce, so any building that relates to the production, storage, transport and/or sale of goods has a good chance of increasing Prosperity. It should be noted that most of these also lower Security. Wherever there is freedom, there is also criminal opportunity. Likewise, Security-devoted buildings such as the Roadblock are one of the few things that can slow the flow of commerce.
As the first item of value is Grain and all wealth stems from the population's ability to feed itself, low Prosperity is directly related to starvation. Allow your Prosperity to level to slip and you are taking the bread from the mouths of your people. Famine will quickly occur if local Prosperity gets too low in populated districts. Alternately, when your people are flush with commerce and material bounty they won't hesitate to throw the settlement a Fair scenario.
The Education happiness represents how well educated your NPC populace is. Neglecting their education entirely will cause them to become slow and inefficient. Allowing your people to educate their children will cause their children become workers more slowly but they will be much more productive when they do join the work-force. The Magic/Science focused Caster classes have actions that can raise the local Education, such as singing Ballads and eventually giving Lectures.
Education can be raised with most buildings that spread and/or gather information. From the Cartographer's Tent to the University, there are many options for spreading knowledge in your Settlement. Conveniently, pursuing Research in your settlement is likely to incidentally increase the local Education rating.
Settlements with completely a completely uneducated population can barely support itself. Tools will break in their hands and falsehoods can spread like wildfire. In this state, a great Ignorance scenario may sweep your people and they'll fail to know how to work entirely. On the other hand, people who have been taught from a young age are effective and innovative members of society. When Education is so high the people are inventing new entertainments, they will throw a Festival to show off.
Respect represents the people's reverence for their leaders and sense of their home's importance. When the city is full of expensive monuments to it's own greatness, the people love their leaders for making their home so awesome. Respect is expensive to acquire, but what's a few tons of Marble for the love of your people?
Many buildings that provide respect are Main buildings of increasingly higher ranked districts. This means that as your Settlement gains in size and importance, the respect of the people for their leaders will grow. Fortunately, rulers feeling insecure can build Statues to their greatness everywhere, provided they have an excess of Cut Gems, Pearls and marble Slabs.
There is no Unhappiness Scenario for Respect. Fortunately, the worst thing an unimpressed populace will do to you is show some disrespect. However, as your settlement achieves opulence, the people start wanting to celebrate how great it is to be your subjects. When their love for you/their home reaches a peak, they will throw a Jubilee in your honor.