Ancient Celtic Mythology:
Shannon & Sinann

Sinann was a goddess in ancient Celtic mythology associated with the river Shannon which is named after her. "Shannon" is how "Sinann" is pronounced, more or less. (I have never understood Irish pronunciation, for example "Eoghan" is "Owen" except in Irish they pronounce all the letters.)

In any case, Sinann was originally a mortal woman who searched for the Well of Knowledge. In this well lived the Salmon of Knowledge, and nuts fallen from nine magical hazel trees. When she found it, in Northern Ireland, she opened the cover and the water flowed out and became the river Shannon. It also killed her and transformed her into the goddess Sinann. This is a special type of myth that explains how places got their names. The Salmon of Knowledge was later eaten, accidentally, by a Celt named Fionn who gained mystical knowledge and became psychic.

I like this story, though it seems sad at first because Sinann dies. This death, though, is the death of death-and-rebirth that changes her into the goddess. In the ancient Celtic world, the search for wisdom was usually made by a woman who found it in a river or well. Always, she is changed by the knowledge into a new being – a goddess.

Another story about Sinann said that she was a slayer of sea monsters. She had a temple on the island of Inis-Cathaig. Later, the Christians had a story about a St. Senan, a man, who killed a sea monster and established a monastery on Inis-Cathaig. Click this line for more on how the gods of ancient Celtic mythology were changed into saints by the Christian church.