#9 - Spain - 32,364,000 Catholics
Christianity in Spain is as old as Christianity itself. It is a well-known fact that Paul wanted to travel all the way to Spain, as it is clear in the fifteenth chapter of his letter to the Romans (verses 24 to 28). Some extra biblical texts (including the Muratorian Canon and the first letter of Saint Clement to the Corinthians) claim Paul in fact reached "the extreme limit of the West". However, if Paul's presence in Spain is a matter of discussion, that of James, the son of Zebedee ("Santiago" being the Spanish evolution of Vulgar Latin Sanctu Iacobu, "Saint James") is one the Spanish hold dear in their hearts: it is believed James himself preached the Gospel all around the Iberian Peninsula, and his body was brought later from Jerusalem (where he was beheaded) to Compostela.
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