"Strictly speaking, there is no such thing as the Roman Catholic Church: there is the One, Holy Catholic and Apostolic Church (which I believe is the official title of the Universal i.e. Catholic Church, with a big ""C""), that comprises 23 sui juris ritual churches, that largest of which is the Western or Latin Church (i.e. the Roman Catholic Church). Therefore his title ought to be ""Pope of the Western Church"". 

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