Roman Catholic
Mary, Queen of Scots was a Catholic and no religion was formed around her.
Queen Mary I was a catholic.
Christian
Mary 1st was a catholic.
catheolic
Catholicism
Mary Queen of Scots was Catholic.
Queen Mary the first brought England back to its original religion.
Queen Mary of Scotland was a devout Catholic who was also tolerant of other religions.
Mary, Queen of Scots was a Roman Catholic.
Protestant
If we are talking about "Bloody Mary"--she suppressed and persecuted non-Catholics.