Cartão Saint Agnes by Domenichino (c. 1620)

Saint Agnes is patron saint of those seeking chastity and purity. She is also the patron saint of young girls and girls scouts. Folk custom called for them to practise rituals on Saint Agnes' Eve (20–21 January) with a view to discovering their future husbands. This superstition has been immortalised in John Keats's poem, The Eve of Saint Agnes.