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The leader of the Jewish faith is called Rabbi.
Muhammad SAW/PBUH is the leader of the islamic faith. When i say leader i mean the founder the person who founded Islam.
The easy answer if they aren't Catholic then they don't believe the Pope is the leader of their faith. The Pope is the leader of the Catholic church.
The vast majority of Europeans are from some denomination of Christianity. Catholicism prevails in some countries, while Protestantism prevails in others.
Brahman
Atahualpa
Atawalpa
She was head of the religious order that she had founded: The Missionaries of Charity.
Iman is not a religios leader. Iman is what Muslims call their faith.
Montezuma II was the leader.
Erik the Red (vikings)
Leif Erikson