Some believe that she is or is related to the ancient Goddess Brigantia or Britannia, while others maintain that they are separate deities. The Romans equated Brigantia and Britannia with their Minerva (and Greek Athena), a deity that has incredibly similar associations to Brighid, so it really is no stretch of thought to consider that Brighid, Brigantia, and Britannia could be related or different variations of the same entity. She is most definitely related to the Catholic Saint Brigid, as their associations mirror each other. This is no surprise considering many Gods and Goddesses were adapted as Saints when the new religion of Christianity came to the British Isles.
Brighid is the daughter of the Dagda, but her mother remains unknown. She is half sister to Oengus, Bo Dearg, and others. Sources often say she is one of three sisters, all named Brighid. While this seems odd to our modern minds, it is a common theme in Celtic mythos. Many deities come in three, three incarnations of themselves. Sometimes they are easily defined separately but related because they have different names and related but different traits, other times not. In this case, the three Brighid sisters are responsible for poetry, healing, and smith craft. The number three is considered an ideal and powerful number. It seems that when something appears in threes, it signifies and amplification of power or importance on that subject or entity.
Brighid is associated with fire, the sun, hearth and home. She brings and cares for new life, spring, healing, cattle and livestock. She breeds and nurtures creativity through poetry, smithing and crafts, wisdom, battle skill, protection, and intelligence. She is truly an all encompassing figure. No wonder she is a favorite!
Her other associations include serpents, boars, wells, and milk. Her holy day is Imbolc, which takes place on February 1st, which is also St. Brigid's Day.
She was married to Bres, a Formiorian, no doubt a political marriage. Her son was named Ruadan, who dies fighting for the Formorians, and through her mourning she invents the practice of keening (crying and singing). She also initiated the use of whistling while traveling at night to keep in good communication.
Brighid has a sacred temple that was tended to by 19 women. No man was allowed to enter. There are stories where a daring man or two decided to test this, and ended up either insane or injured. Other stories include her birth and adoption by Druids and Christians, her healing abilities, and her wit. often the lines between Goddess, Druid, and Saint are blurred. There are many stories, and if you would like to read more about them or about Brighid herself, I humbly encourage you to read this book: Brigid: Goddess, Druidess and Saint
.