Manawydan fab Llyr is a figure of
Welsh mythology, the son of
Llyr and the brother of
Brân the Blessed and
Brânwen. The first element in his name is cognate with the stem of the name of the
Irish sea god
Manannán mac Lir, and likely originated from the same Celtic deity as Manannán. Unlike Manannán, however, no surviving material connects him with the sea in any way except for his patronymic (
llyr is an old Welsh word for
sea). Manawydan's most important appearances occur in the Second and Third
Branches of the Mabinogi (the later of which is named for him), but he is also referenced frequently in medieval poetry and the
Welsh Triads.