Becoming Suzerain of City-States in is a fairly straightforward process if you know what you are doing, but the process might be a little difficult to figure out without being somewhat familiar with the in-game menus and UI. Becoming Suzerain of a City-State opens up unique gameplay options with the Independent Power and can give you strategic advantages throughout the Ages. City-States are Age-specific, meaning they reset at the beginning of each Age. However, City-States can also be incorporated into their Suzerain's empire, or overthrown and razed, just like any other major Settlement would.
Independent Powers, which can be turned into City-States using Influence, are automatically loaded into each Age with unique bonuses based on specific categories that happen to sync up with the four Legacy Paths: Military, Gold, Science, and Culture. When you first interact with a unit from an Independent Power, they will be hostile, neutral, or friendly. Any civilization in the campaign can improve its relationship with a given Independent Power, and it's first come, first served, meaning once someone claims an Independent Power, it's under their control for at least forty turns.
At the start of all three Ages, Independent Powers spawn on the map randomly and can be interacted with as you explore. After unveiling an Independent Power's location, leaders can select the Befriend Independent option from the Leader menu under the Independents & City-States tab (the Heart icon).
The addition of Discoveries during the Antiquity Age will make choices matter in Sid Meier's Civilization 7, more so than the goody huts from Civ 6.
From there, a set amount of Influence can be spent to befriend the Independent Power over the course of several turns, whichtakes longer depending on their hostility level.
As Independent Powers become more friendly, hostile units will stop attacking, a one-time resource bonus is awarded, and the Independent Power becomes a City-State with the leader who
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