Leaders

§ Each civilization in Civilization IV has one or two leaders available to lead it. When you start a game of Civ, you will pick which civilization you want to lead; if that civilization has two available leaders, you pick them which of them you want to play. Each computer-controlled civilization has a leader as well.
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Leader Personalities

§ When you control a leader, you determine how your leader interacts with the world around him or her. Is the leader honest or shifty? Is the leader open, or paranoid? Is the leader aggressive or peaceful? It's up to you. When the computer controls a leader, the computer determines the leader's behavior. Often, the leader behaves like his or her historical counterparts - but don't count on it. Gandhi will USUALLY be peaceful and friendly, but he may from time to time turn out to be a warmongering backstabber. You have been warned!.
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Leaders and Diplomacy

§ A leader's personality and his or her interpretation of the current game situation will determine how the leader negotiates with you. Further, leaders have long memories; if you deal fairly with them, they'll remember it. And if you betray them, they'll remember that, as well. Check out Diplomacy for more information on this topic.
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Leader Traits

§ Leaders in Civilization have "traits" which help determine the kind of civilization they are best at running. Each leader has two of the following traits:
§ Aggressive
§ Free "Combat I" Promotion for melee and gunpowder units.
§ Creative
§ +2 Culture per city per turn.
§ Expansive
§ +2 Health Points per city.
§ Financial
§ +1 Commerce on any squares which normally produce two or more commerce.
§ Industrious
§ +50% Wonder production.
§ Organized
§ -50% Civic Upkeep cost.
§ Philosophical
§ +100% Great Person birth rate.
§ Spiritual
§ No anarchy from changing civics.
§ Each trait also allows civilizations that possess it to construct some buildings at double speed; for example, leaders with the Philosophical trait build Universities twice as fast.
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Leader List

§ Check out the Leader List for a complete list of the leaders in Civilization IV, their game traits, and historical backgrounds.
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