*This page last updated: 15 December, 2017 13:56 PST. (Log of recent changes)
Disclaimer: The information listed below is about a game that is still under development, and so is incomplete and subject to change.

Civics now behave very much like a second technology tree, with each new civic gradually unlocked by accumulated Culture. Each Civic unlocks one or more items, including policies, district or building types, wonders, and government types. Each government type has a varying number of color-coded slots for policies, and you can mix and match which policies to place in which slot. The starting "Chiefdom" government type has one military slot and one economic slot; later government types have more and different slot types. There are four policy slot types: Military, Economic, Diplomatic, and Wildcard (which is a policy type, in addition to a slot type).

"There were always a lot of things in the tech tree like 'chivalry' that weren't really a technology." - Ed Beach

The "Eureka" objective system that applies to research also applies to Civics (though they are called "Inspirations"); completing these objectives will add huge culture credits toward earning that particular civic.

Civics are divided into the same eras as Technologies are, and you can advance to the next era via Civics instead of technologies.

 

Civics Tree

Here is a full version from the current patch (November 2017):

Click on the image for a larger version.

Tree Analysis

There are hidden bonuses for each Civic that are not listed in the tree view. I will list these in the "Other" column as I find them. The research costs here are based on Quick game speed, but should be viewed with suspicion and as a relative measure only.

Civic Cost Era Unlocks Boost Other
Code of Laws 20 Ancient Survey, Discipline, Urban Planning, God King -  
Craftsmanship 40 Ancient Ilkum, Agoge Improve 3 tiles. -
Foreign Trade 40 Ancient Trader unit, Maritime Industries, Caravansaries, Join War agreement Discover a second continent. Allows Trade Routes.
Military Tradition 50 Ancient Strategos, Maneuver Clear a Barbarian outpost. Grants flanking and support combat bonuses to all units.
State Workforce 70 Ancient Conscription, Corvée Build any district. -
Early Empire 70 Ancient Colonization, Land Surveyors, Open Borders agreement Grow your civilization to at least 6 population. Unlocks the ability to enforce borders and grant Open Borders.
Mysticism 50 Ancient Oracle, Inspiration policy, Revelation policy Found a Pantheon Awards 1 Envoy
Games and Recreation 110 Classical Colosseum, Arena, Entertainment complex, Insulae policy Research the Construction technology.  
Political Philosophy 110 Classical Autocracy, Classical Republic, Oligarchy, Charismatic Leader, Diplomatic League Build a wonder.  
Drama and Poetry 110 Classical Amphitheater, Theater Square, Literary Tradition policy    
Military Training 120 Classical Raid policy, Veterancy policy Build an Encampment Awards 1 Envoy
Defensive Tactics 175 Classical Limes policy, Bastions policy Be the target of a Declaration of War.  
Recorded History 175 Classical Great Library, Natural Philosophy policy Build 2 Campus districts.  
Theology 120 Classical Temple, Mahabodhi Temple, Scripture policy Found a Religion. Awards 1 Envoy, obsoletes God King policy
Naval Tradition 200 Medieval Naval Infrastructure, Navigation Kill a unit with a Quadrireme Awards 1 Envoy.
Feudalism 275 Medieval Feudal Contract policy, Serfdom policy Build 6 Farms. +1 Food for each farm when 3 are adjacent. Obsoletes Agoge, Ilkum
Civil Service 275 Medieval Retainers policy, Meritocracy policy, Alliance agreement Grow a city to 10 population. Allows Alliances.
Mercenaries 290 Medieval Professional Army, Sack, Trade Confederation Have 8 land combat units in your army. Awards 1 Envoy
Medieval Faires 385 Medieval Medina Quarter, Aesthetics, Merchant Confederation Maintain 4 Trade Routes. Obsoletes Insulae
Guilds 385 Medieval Chichen Itza, Craftsmen, Town Charters, Traveling Merchants Build 2 Markets -
Divine Right 290 Medieval Mont St. Michael, Monarchy, Chivalry, Gothic Architecture Build 2 Temples Obsoletes Corvee, Maneuver
Exploration 400 Renaissance Merchant Republic, Native Conquest, Colonial Offices, Mission Build 2 Caravels. +1 Food from Pastures. Obsoletes Discipline, Survey, Urban Planning
Humanism 540 Renaissance Archaeological Museum, Art Museum, Frescoes, Invention Earn a Great Artist. Obsoletes Revelation
Diplomatic Service 540 Renaissance Machiavellianism, Spy unit, Resident Embassies agreement, Declare Holy War, Declare Liberation War, Declare Reconquest War, Declare Protectorate War Have an alliance with another civilization Allows Resident Embassies and your first Spy. Casus Belli may now be used to justify wars.
Reformed Church 400 Renaissance Theocracy, Religious Orders, Simultaneum, Wars of Religion Have 6 cities following your Religion.  
Mercantilism 655 Renaissance Privateer, Logistics, Triangular Trade Earn a Great Merchant +1 Production from Camps, Obsoletes Caravansaries
The Enlightenment 655 Renaissance Free Market, Liberalism, Rationalism Earn 3 Great People. Religious Tourism effects are halved versus your civilization.
Colonialism 690 Industrial Colonial Taxes, Press Gangs, Raj Research the Astronomy Technology Awards 1 Envoy. Obsoletes Maritime Industry
Civil Engineering 875 Industrial Public Works, Skyscrapers Build 7 different specialty districts Can build Farms on Hills. All cities gain +200 Fortification strength and bombardment ability. Obsoletes Bastions, Corvee, Gothic Architecture, Limes, Serfdom
Nationalism 875 Industrial Grande Armee, National Identity, Declare Colonial War Declare war using a casus belli. +1 Spy slot. Unlocks Corps and Fleets. Obsoletes Feudal Contract
Opera and Ballet 690 Industrial Bolshoi Theatre wonder, Grand Opera, Symphonies Build an Art Museum. Awards 1 Envoy.
Natural History 830 Industrial Archaeologist, Zoo, Hermitage, reveal Antiquity Sites Build an Archaeological Museum. Awards 1 Envoy
Urbanization 1010 Industrial Neighborhood district, Military Research, Public Transport Grow a city to 15 population.  
Scorched Earth 1010 Industrial Expropriation, Military Organization, Total War Build 2 Field Cannons. Awards 1 Envoy. Obsoletes Colonization, Land Surveyors, Raid, Sack, Strategos
Conservation 1140 Modern Naturalist unit, Resource Management policy, National Parks Have a Neighborhood district with Breathtaking Appeal. Awards 1 Envoy. Builders may plant Woods. Old growth Woods gain +1 Appeal.
Mass Media 1280 Modern Cristo Redentor, Broadway, Propaganda Research Radio. Obsoletes Retainers
Mobilization 1280 Modern Levee en Masse policy, Defensive Pact agreement, Declare War of Territorial Expansion Have 3 Corps in your army. Unlocks Army and Armada. Obsoletes Conscription
Capitalism 1420 Modern Laissez-Faire, Market Economy Build 3 Stock Exchanges. Obsoletes Trade Confederation, Traveling Merchants
Ideology 600 Modern Police State policy - +1 Spy slot
Nuclear Program 1560 Modern Nobel Prize, Nuclear Espionage Build a Research Lab. Obsoletes Inspiration
Suffrage 1560 Modern Democracy, Arsenal of Democracy, Economic Union, New Deal, Their Finest Hour Build 4 Sewers. Obsoletes Liberalism, Medina Quarter, Naval Infrastructure, Town Charters
Totalitarianism 1560 Modern Fascism, Gunboat Diplomacy, Lightning Warfare, Martial Law, Third Alternative Build 3 Military Academies. Obsoletes Charismatic Leader, Chivalry, Maneuver
Class Struggle 1560 Modern Communism, Collectivization, Defense of the Motherland, Five-Year Plan, Patriotic War Build 3 Factories. Obsoletes Craftsmen, Natural Philosophy
Cultural Heritage 1700 Atomic Sydney Opera House, Heritage Tourism, reveal Shipwreck resource Have 3 Themed Museums, Awards 1 Envoy
Cold War 1900 Atomic Containment, Cryptography, International Waters Research the Nuclear Fission technology. +1 Spy slot. Obsoletes Maritime Industries, Press Gangs
Professional Sports 1900 Atomic Maracanã Stadium, Stadium, Sports Media Build 4 Entertainment Complex districts. Obsoletes Aesthetics, Grand Opera
Rapid Deployment 2100 Atomic Military First Build an Aerodrome or Airstrip on a foreign continent. Allows airlift between Airports. Obsoletes Grand Armee.
Space Race 2100 Atomic Integrated Space Cell, Satellite Broadcasts Build a Spaceport district. Obsoletes Military Research
Globalization 2400 Information Ecommerce, International Space Agency, Strategic Air Force Build 3 Airports. +1 Gold to Plantations. Obsoletes Their Finest Hour, Triangular Trade. Repeatable for additional Score.
Social Media 2400 Information Collective Activism, Online Communities Research the Telecommunications technology. Repeatable for additional Score.

 

Governments

Known government types and their associated bonuses and policy slot types:

Government Inherent Bonus Legacy Bonus Social Policy Slot Types
Chiefdom (none?) (none?) 1 military, 1 economic
Classical Republic All cities with a district receive +1 Amenity +X% Bonus Great People point generation. 2 economic, 1 diplomatic, 1 wildcard
Oligarchy All melee units gain +4 Combat Strength +X% Combat experience for units. 1 military, 1 economic, 1 diplomatic, 1 wildcard
Autocracy Capital receives +1 boost to all yields +X% bonus on wonder production. 2 military, 1 economic, 1 wildcard
Monarchy +2 Housing in any city with Medieval Walls. +X% bonus influence points generation. 3 military, 1 economic, 1 diplomatic, 1 wildcard
Theocracy Can buy land combat units with Faith. All units +5 in theological combat. +X% discount on Faith purchases. 2 military, 2 economic 1 diplomatic, 1 wildcard
Merchant Republic +2 Trade Routes. +X% discount on gold purchases. 1 military, 2 economic, 1 diplomatic, 2 wildcard
Democracy Patronage of Great People costs 50% less gold. +X% bonus yield from district projects. 1 military, 3 economic, 2 diplomatic, 2 wildcard
Communism Industrial Zone Districts can defend. Land units gain +4 defense strength. +X% bonus on all types of production. 3 military, 3 economic, 1 diplomatic, 1 wildcard
Fascism All combat units gain +6 attack strength. +X% bonus on unit production 4 military, 1 economic, 1 diplomatic, 2 wildcard


All government and social policy changes are free on the turn that a new Civic is completed.

The "Legacy Bonus" is a % bonus that accrues the longer you stay with a particular government, but which you keep even if you later change governments.

"We allow you to re-slot policies for free every time you complete a Civic. You can do it anytime you want, it just costs some gold if you're doing it between turns. For a culture player, there's a large amount of Military-specific policies that you can get. If you're a Military-focused player, you might not have as deep a lineup of policies, because you're mainly playing science. As a culture player, you'll have those abilities. You'll be able to produce units 25 percent faster as an example. You can react to stuff pretty quickly. If you're really far behind there may be no hope, but there's a lot of knobs a player can turn to get a lot more defensive ability." - Dennis Shirk

Social Policies