I've just read the first rune of the Kalevala (Crawford's translation). Most of it is about the "maiden", "daughter of the Ether", and how her travels in the sea lead to the creation of the world. It is mentioned that she has a baby, but nothing more about that baby:
Seven hundred years she labored
Ere her first-born was delivered.
Thus she swam as water-mother,
Toward the east, and also southward,
Toward the west, and also northward;
Swam the sea in all directions,
Frightened at the strife of storm-winds,
Swam in travail, swam unceasing,
Ere her first-born was delivered.
Later in the poem, after the world has been created, the story shifts abruptly to Wainamoinen:
Thus created were the islands,
Rocks were fastened in the ocean,
Pillars of the sky were planted,
Fields and forests were created,
Checkered stones of many colors,
Gleaming in the silver sunlight,
All the rocks stood well established;
But the singer, Wainamoinen,
Had not yet beheld the sunshine,
Had not seen the golden moonlight,
Still remaining undelivered.
Wainamoinen, old and trusty,
Lingering within his dungeon
I've read enough about the Kalevala to know that he is the baby mentioned earlier. The title of this rune is also "The Birth of Wainamoinen". But how is this clear from the writing itself, without any external context? The baby is mentioned briefly early in this rune, and at the later stage it seems as though we're shifting locations from the maiden in the sea to a man in prison.
Is it meant to be clear, without context, that Wainamoinen is the son? How?