Jennifer Lawrence (author of Washerwoman, in The Phantom Queen Awakes) writes:
I’ve mentioned in my last post that I already knew of the Morrigan from a life-long love of mythology. When most people say they know a bit about mythology, they generally refer to Greek and Roman myths, often picked up from required reading in grade school. Or they might have been required to read the Iliad or the Odyssey in high school.
Not a lot of people are familiar with Celtic mythology, despite the big craze for all things Celtic during the 90’s. Celtic mythology can be a peculiar thing. It’s nowhere as neatly ordered as Greek mythology—no single god of the sun, god of war, or king/father god. Sure, the Tuatha de Danaan had a king god in Nuada. Then he lost one of his hands in battle, and the taboo the pantheon had which said that a king must be physically perfect kicked in, and he could no longer be their king. Leadership of the Tuatha passed to Bres, who was a perfect tyrant, favoring their foes, the Fomorians. When Dian Cécht, the god of healing for the Tuatha replaced Nuada’s missing hand with one crafted of pure silver, he became their king again—until he died, at which point, the kingship passed to Lugh, god of generalities. After Lugh, the Dagda became king, and then another and another.
This multiplicity of roles is common among the Tuatha de Danaan. Both Brigid and Goibhniu were considered smithing deities; Brigid also shared the area of healing with Dian Cécht. The ancient Irish had both a god of love, in Aengus, and a goddess of love, in Áine. In like manner, there is no single deity who rules over death. The Morrigan is considered the goddess of death, especially on the battlefield, but Manannán mac Lir is the Psychopomp for the pantheon, conducting the souls of the deceased to islands of the dead.
Some folks might think that difficult to remember, in comparison to the neatly-ordered spheres of influence of the Greek gods. The ancient Irish certainly did not seem to, however; aside from the better-known deities I’ve listed, they had dozens, perhaps hundreds of others, both major and minor—everything from the great mother goddess Danu, who gave her name to the pantheon (the Tuatha de Danaan, or ‘children of Danu’) to countless gods and goddesses of fields, rivers, and mountains, many of whose names and histories have been lost to modern time. The ancient Irish, unlike the Greeks and Romans, didn’t start writing down their histories and tales until well after the advent of Christianity in that country. As you might imagine, the monks weren’t whole-heartedly interested in preserving the stories of the land’s pagan, pre-Christian gods. But some of those stories did get written down, and if more was lost than kept, we are still the richer for it today.