The Envoy is a representative of your civilization that can be sent to city-states that you've met. By default, one Envoy is earned for every 100 influence points that you accumulate. After earning an Envoy, you will receive a prompt to choose which city-state to send it to. If you have multiple Envoys, you may divide them between city-states as you wish.
The bonuses you earn from a city-state depend on how many Envoys you have sent to the city-state. One bonus is earned for having 1 Envoy, the next bonus is at 3 Envoys, and the final bonus is at 6 Envoys. The civilization with the most envoys on a city-state, and at least 3 envoys, is considered that city-state's Suzerain, which gives additional bonuses.
Declaring war directly on a city-state removes all Envoys you had there. Otherwise, Envoys stay on the city-state permanently. Envoys at a city-state are visible to all players, and placing them may have diplomatic consequences. The bonuses earned are based on how many Envoys you have present, regardless of who else has Envoys there. City-states of a type all share the same type of bonuses. They are cumulative, so that as a player places more and more Envoys on a city-state, they stack with the bonuses from before.
- Influence generates Envoys over time. Check here for more information.
- Additionally, the government Monarchy grants an additional 20% to your influence generation, +1% every ten turns on Standard speed. The diplomatic policy card Charismatic Leader grants 2 influence per turn. This gets replaced by Gunboat Diplomacy that ups it to 4 per turn.
- Being the first to meet a city-state grants one Envoy.
- Completing city-state quests grants one Envoy.
- The diplomatic policy card Diplomatic League doubles your first envoy to a city state. To min-max this, you can store up envoys until you have met a certain number of city-states, then activate the card and get the bonus for each one, and then deactivate the card since it no longer gives benefit.
- The diplomatic policy card Containment doubles envoys to City-States whose Suzerain has a different government. This could be min-maxed in a similar way to Diplomatic League; just remember that you lose the bonus once you become Suzerain.
- Some Great General retirement and Great Merchants powers provide Envoys.