While a core part of the Ages structure in Sid Meier's Civilization 7 are the four main Legacy Paths and their powerful bonuses at the start of the Exploration and Modern Ages, there are also unique Dark Age bonuses that can only be acquired by failing to complete any of the milestones in a given path. These Dark Age bonuses are distinct in that they provide powerful advantages but also include a penalty of some sort. These Dark Age bonuses can be planned for and used strategically or may come as a lifeline if you find yourself in dire straits.
Dark Ages are only awarded for the Antiquity and Exploration Ages, as there are no Ages to apply a Dark Age bonus to after the Modern Age (at least for now). These bonuses have distinct use cases and will not be helpful in all situations, but they can also allow you to "catch back up" if you have fallen significantly behind other civilizations. Knowing what each Dark Age does may come in handy if it's necessary to pivot during an Age transition and offer an alternative if no Golden Age bonuses are available.
Antiquity Dark Ages & How To Use Them
Only One Dark Or Golden Age Can Be Selected Each Age
If you fail to complete any milestones in any of the four Legacy Paths, a Dark Age becomes available at the beginning of the next Age. Only one Dark Age or Golden Age bonus can be selected, and each Dark Age includes a penalty of some kind. For example, the Cultural Dark Age in Antiquity provides Missionaries in the Exploration Age an additional charge but imposes a Happiness penalty in all Settlements once you have founded a Religion in Civ 7. This can be useful if you fail to construct any Wonders in the Antiquity Age, have a surplus of Happiness, and wish to pursue the Cultural Legacy Path.
The Scientific Dark Age is unlocked by completely failing to acquire a single Codex in the Antiquity Age. It provides a free Technology every five turns in Exploration, but cuts Science output in half. Depending on the circumstances or strategy, Science may not be a focal point, and you might actually unlock more technologies in the Exploration Age than you would otherwise with this Dark Age in place. The Antiquity Scientific Dark Age guarantees access to Technologies, even if it is random, which can aid tremendously if Science yields are an issue.
Cultural |
Missionaries have +1 charge and +1 movement. |
Minus three Happiness in all Settlements once you have founded a religion, doubled if the Settlement does not follow your religion. |
Scientific |
Gain a random Technology boost every five turns. |
Minus 50% Science. |
Military |
Gain three fully packed cavalry armies with siege. |
Lose all of your existing armies and all of your settlements except your capital. |
Economic |
Naval Commanders gain a charge to create a new Settlement for every two levels earned. |
Settlers cost 100% more. |
The Military Dark Age in Antiquity is a tough choice, but could very well have a crucial impact in specific situations, awarding three fully packed Cavalry armies at the start of Exploration at the hefty cost of sacrificing ALL existing armies AND Settlements, aside from the Capital.
This bargain could pay off handsomely, especially if playing as Charlemagne or starting Exploration as Mongolia.
Where most civilizations in the Exploration Age have to travel to the Distant Lands for Military Legacy Points, Mongolia earns points on the home continent, so starting with only the capital and a horde of cavalry units might not be a bad play after all.

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Finally, the Economic Dark Age in Antiquity gives Naval Commanders the unique ability to establish settlements for every two levels you advance, but it will increase the cost of Settlers by 100%. Establishing Settlements in the Distant Lands can be quite advantageous, especially if planning to wage war to conquer Settlements anyway. On the other hand, it could help establish Treasure Fleets more quickly and help pivot away from a militaristic to an economic approach. Each Antiquity Dark Age sets you up for a unique play style during the Exploration Age and could potentially turn the tide entirely.
Exploration Dark Ages & How To Use Them
Exploration Dark Ages Open Up New Opportunities For Victory

Once you reach the Modern Age, these Exploration Dark Ages might act as a lifeline, just as they did at the end of Antiquity, but in this case, the stakes are a bit higher. Victories in Civ 7 are achieved most easily by completing as many milestones along a given Legacy path in each Age as possible. But if everyone in the campaign has been ignoring a particular path, this might be the time for a Hail Mary. For example, the Cultural Dark Age in Exploration allows Explorers to unearth Artifacts faster at the cost of Influence, providing a viable path toward the World's Fair Wonder.
The Scientific Dark Age unlocks Flight very early in the Technology tree (with Combustion), also increasing the cost of airplanes, but has the potential to speed you along your progress in the Space Race Projects. Flight unlocks the first Space Race Project, and accessing it early means a jump start in the Space Race. Alternatively, this might provide you focusing an opportunity to establish an air force early in the Modern Age, assuming Gold or Production are abundant - the Exploration Scientific Dark Age penalty increases the cost of airplanes considerably.
Cultural |
Explorers get +1 movement speed and unearth Artifacts 50% faster. |
- 50% Influence. |
Scientific |
Flight is unlocked with Combustion. |
+ 50% cost to all airplanes. |
Military |
Gain two free levels on all Commanders and new Commanders start with two additional levels. |
All military units cost 25% more. |
Economic |
Plus 100% Production and Gold towards Rail Stations and Ports, and +1 resource slot in all Settlements. |
- 25% Culture. |
The Military Dark Age in Exploration gives all Commanders two free promotions, and each new Commander starts with two additional levels, making it a viable option for a pivot toward the Ideology Legacy Path. Assuming Gold or Production are not in short supply, the increased cost of units will be negligible. Similarly, the Economic Dark Age allows you to establish railroads and ports in your trade network, working toward the Great Bank victory. If you aren't concerned about Cultural progress, this might be a useful option.

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Overall, there are many different situations where these Dark Ages could come in handy. Civilization 7's Dark Ages are not for the average playthrough and will likely not be part of most players' initial strategies, but with a clear understanding of what they do, Dark Ages can provide a unique advantage.

Grand Strategy
Turn-Based Strategy
4X
Released February 11, 2025
ESRB t
Franchise Sid Meier's Civilization
Developer(s) Firaxis Games
Publisher(s) 2K