The Religious victory is a victory condition new to Civilization VI and replaces the old Diplomatic victory from Civilization V. This victory requires mastering diplomatic relationships in order to convert civilizations.
Check out the brand new online multiplayer mode, Red Death, available now as part of the September 2019 update for all Civilization VI players on PC. Civ VI's Districts offer more flexibility in city planning, and introduce different considerations when expanding your empire. In the early game especially, you should aim to have access to Fresh Water (Rivers / Lakes), or Coasts from your City Center, as Housing is the biggest cap on early game growth.
To achieve a Religious victory, a player's Religion must become the predominant Religion for every civilization in the game.
A Religion is predominant if it is followed by more than 50% of the cities in a civilization.
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Religion allows players to build Inquisitors and Apostles . To achieve a Religious victory, a player's Religion must become the predominant Religion for every civilization in the game, both for major and minor civilizations.