Suspect 4 - St. Patrick
The patron saint of Ireland, St. Patrick is inseparable from the Irish identity. Traditionally known as the person who brought Christianity to this island, this holy man from history, while having a certain reputation with regards to his dislike of snakes, would otherwise be identified with the Christian message of peace and love. Surely not the sort of person to poison someone, particularly a guy like Santa.
Mind you, when we describe people as saints, we should remember that doesn’t necessarily mean harmless or indeed peace loving. For instance another Irish saint St.Colmcille, allegedly started a war between two tribes, for which he was exiled. Even St. Paul, one of the fathers of Catholicism, was a known persecutor of Christians and personally oversaw many executions before he changed his ways. Saints can be not only complicated people, but equally quite violent.
Fun Fact – St. Patrick is most famous for being credited for bringing Christianity to Ireland, for allegedly ridding the county of snakes and has always been proud that he is the only saint in the National Wax Museum.