An
antipope is a person who, in opposition to the one who is generally seen as the legitimately elected
Pope, makes a significantly accepted competing claim to be the Pope, the
Bishop of Rome and leader of the
Roman Catholic Church. At times between the 3rd and mid-15th century, antipopes were supported by a fairly significant faction of religious
cardinals and secular
kings and kingdoms. Persons who claim to be pope, but have few followers, such as the modern
sedevacantist antipopes, are not classified with the historical antipopes.