What we know about Manannán mac Lir from Irish myth (a partial list):
- He initially appears as a king of Emhain Abhlac (an Otherworldly island) across various stories in the Mythic cycle
- He is incorporated as one of the Tuatha De Danann by the 11th century (the Fenian cycle of myths)
- The Cóir Anmann calls him a god of the sea
- He helps the Tuatha De Danann to go into the sidhe and teaches them how to live there and to pass invisibly to mortals (Lebor Gabala Erenn)
- He ruled as co-king of the TDD with Bodb Dearg (Altram Dá Tige Medar)
- His father is given as Elloth in the Lebor Gabala Erenn but later as Lir; it is likely that 'mac Lir' was originally an epithet related to his skill on the ocean
- His wife in the Ulster Cycle is Fand, and he appears in Serglige Conchulainn after Fand falls in love with Cu Chulainn to use magic so that the two will forget each other, in order to end the rivalry between Fand and Cu Chulainn's wife Emer.
- His wife according to folklore in Cork is the Cailleach
- Or his wife might be Áine, but alternately she might be his daughter
- other children include Niamh, Cliodhna (maybe), Curcog, and a son named Ilbreac
- Lugh is his foster-son, and in the Oidheadh Chloinne Tuireann several of Manannán's possessions are held by Lugh, including both his horse and his curragh.
- He travels to the human world in order to father Mongan, a figure in the Cycle of Kings
- One of his greatest and most well known treasures is the crane bag, which was made from the skin of Aoife who had been turned into a crane by a romantic rival. This bag held an assortment of magical treasures that belonged to Manannán (Dunaire Finn)
