Saint Irene is considered the patron saint of the city of Tomar. A martyr of the 7th century, she was born in the city of Nabância, Tomar’s predecessor, in the year 635. She grew up in a Christian family and decided to pursue religious life in a Benedictine convent, ruled by her uncle, the Abbot Celio.
Britaldo, son of the lord of the land, saw Iria and fell madly in love with her. When he fell ill with love, he was visited by Iria who, feeling sorry for him, asked him to forget her because she wanted to devote herself to God alone, and promised never to give herself to anyone.
Besides Britaldo, Friar Remigio could not remain indifferent to Irene’s beauty. Tormented with jealousy, he gave her a medicine that made her belly swell up, as if she were pregnant. Iria was later expelled from the convent, presumably for having broken her chastity vows. Knowing what had happened, and feeling betrayed, Britaldo beheaded her by the Nabão River and threw her body into the waters.
 
Carried by the waters to the Tagus River, Iria’s body was found uncorrupted near the city of Scallabis (now Santarém). She was then buried in a marble tomb and, due to her great devotion, the city of Scallabis was renamed Santarém in her honour.
Six centuries later, the Tagus waters opened again to reveal the tomb to King Dinis and Queen Saint Elizabeth, whose memorial monument stands by the Tagus, with the image of Saint Irene protecting the riverside people from the cyclic floods that used to affect them.
The evocation of Saint Irene is held annually by the people of Tomar on 20th October, the day when flower petals are thrown into the Nabão River, in remembrance of her martyrdom. In homage to its patron saint, Tomar still holds the Santa Iria Fair, created in 1626 by King Philip III as a fair for peddlers, grocers, goldsmiths, shoemakers, potters, and fishmongers, currently enriched with the Raisin Fair.