Manannán mac Lir connects with Manawydan fab Llŷr
Manannán or Manann, also known as Manannán mac Lir ("son of the sea"), is a warrior and king of the Otherworld in Irish and Manx mythology who is associated with the sea and often interpreted as a sea god, usually as a member of the Tuatha Dé Danann.
He is seen as the ruler and guardian of the Otherworld, and his dominion is referred by such names as Emain Ablach, Mag Mell (Plain of Delights), or Tír Tairngire (Land of Promise). He is described as over-king of the surviving Tuatha Dé after the advent of humans (Milesians), and uses the mist of invisibility (féth fíada) to cloak the whereabouts of his home as well as the sidh dwellings of the others.
In modern tales, he is said to own a self-navigating boat named Sguaba Tuinne ("Wave-sweeper"), a horse Aonbharr which can course over water as well as land, and a deadly strength-sapping sword named Fragarach, though the list does not end there.
Manannán appears also in Scottish and Manx legend, where he is known as Manannan mac y Leir ("little Mannan, son of the sea"). The Isle of Man (Mannin) is named after him, while others say he is named after the island. He is cognate with the Welsh figure Manawydan fab Llŷr.Familial relations
Manannán's father is the sea-god Ler ("Sea; Ocean"; Lir is the genitive form), whose role he seems to take over. As Oirbsen, his father is named as Elloth, son of Elatha. In the Altram Tige Dá Medar Manannán calls himself the foster-son of the Dagda.According to Táin Bó Cúailnge (the Cattle Raid of Cooley), his wife is the beautiful goddess, Fand ("Pearl of Beauty" or "A Tear" – later remembered as a "Fairy Queen", though earlier mentions point to her also being a sea deity). Other sources say his wife was the goddess Áine, though she is at other times said to be his daughter. Manannán had a daughter, whose name was Niamh of the Golden Hair. It is also probable that another daughter was Clíodhna, but sources treat this differently. Either way, she is a young woman from Manannán's lands, whose epithet is "of the Fair Hair". Manannán also had a yellow-haired daughter given the "baptized" name Curcog (meaning "beehive" or "bushy tuft") who was given up to be fostered by Aengus.Manannán is also given sons named Eachdond Mor and Gaidiar, who raped Becuma Cneisgel.Another daughter of Manannán's was said to be Saint Athrachta; according to oral legend, she tried to build a causeway across Lough Gara by carrying large stones in her petticoat but was prevented by modesty. In another legend of Athractha, she was said to live at the bottom of Lough Gara and only emerged every seven years to visit her sister Cé (Ké). Athractha cured a woman, and once a dragon with the roar of a lion emerged from the sludge and was vanquished by the Holy Virgin. There is also folklore that Cé (or Céibh) the daughter of Manannan lost her beauty and wits due to an incantation, but recovered her beauty after Oísin provided her hospices after others all shunned her.In The Voyage of Bran, Manannán prophesied to Bran that a great warrior would be descended from him. Thus Mongán mac Fiachnai becomes a late addition to the mac Lir family tree. The historical Mongán was a son of Fiachnae mac Báetáin, born towards the end of the 6th century. According to legend Fiachnae, who was at war in Scotland, came home with a victory because of a bargain made with Manannán (either by him, or by his wife) to let Manannán have a child by his wife. This child, Mongán, was supposedly taken to the Otherworld when he was very young, to be raised there by Manannán. The 8th-century saga Compert Mongáin tells recounts the deeds of a legendary son, In the Dinsenchas Manannán is also described as the father of Ibel, after whose death Manannán cast draughts of grief from his heart that became Loch Ruidi, Loch Cuan, and Loch Dacaech.Manannán is often seen in the traditional role of foster father, raising a number of foster children including Lugh of the great hand and the children of Deirdre.
Two brothers of Manannán are named, after whom cleared plains were named - Bron, who it is implied was slain by Fergus and Ceite. Similarly, in Welsh folklore Brân the Blessed is the brother of Manawydan.