In early times, the first Popes would keep their baptismal names. But John II, who's birth name was Mercurius, and served as Pope from 533-535, was the first to change his name. After him, all men elected Pope have chosen another name to go by during their pontificate.
Why do the Popes choose a new name?
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In early times, the first Popes would keep their baptismal names. But John II, who's birth name was Mercurius, and served as Pope from 533-535, was the first to change his name. After him, all men elected Pope have chosen another name to go by during their pontificate.