The stealing of the light.

"A long, long time ago, when the earth was still so new it was soft, Raven lived. And, for the most part, the world was good, except there was no light.
And, in the dark, no one could see anyone, and the spirits could not see their bodies, and all the people and animals spent a great deal of time stumbling around sightlessly. It was through this dark that Raven was flying when he happened to see something strange.
A light.
It was coming through the window of the house of a jealous old man. The man was holding a large box, and through the cracks leaked out a pure, bright light. Raven knew at once he needed this light for the world, but he also knew the jealous old man would never let him into his house. But Raven was not troubled by this, because the old man had a daughter.

'Raven Steals the Light' by Bill Reid

Raven transformed himself into a grain of sand, and flung himself into the river from which the man and his daughter drank every day. When the daughter scooped some of the cold water into her mouth, Raven was there, and slid down her throat with ease, and settled into her stomach.
Over the coming months the man's daughter found herself inexplicably with child. When she gave birth, it was not to a raven, or a human, but a Raven Child, with feathers and fingers and a beak and claws. But of course no one could see this because everything was dark.
The old man was very fond of this Raven Child, and couldn't deny him anything. The Raven Child begged every day to play with the box that contained the light, and the man gave it to him, but the man was not as foolish as Raven had originally thought. The light was in a box, but the box was in another box, which was in another box, in another box, in another box... and the Raven Child could only manage to pry off the outermost box before the old man would snatch the rest away and stow them up high were even the tricky Raven Child could not reach them.
Finally, many many days later, the Raven Child knew he was on the last box. It was small, but it was warm and heavy in his hands. He pried it open, but no sooner had he caught the light than the jealous old man pounced after him, seeing at last the Raven Child's trickery.
But the Raven Child was too quick for him. At once he was Raven in his original form again, and he fled away with the light up the chimney pipe and into the open sky.
But now that the light was in the sky, every wandering body of beast and man, and every lost soul that had been floating around in the dark, raced towards the light with a mothlike desperation. And Raven tried to outfly them, but the light was so heavy, and soon Eagle—fastest of them all— was right on his tail-feathers, snatching at him, and Raven dropped the light, and it fell to the ground and shattered into two pieces, and the smaller piece and all the shards bounced back up into the night, and Raven, acting fast, took the larger piece and threw it into the day.
He threw it so high that no one could ever reach it, but he also threw it so high that no one could ever take it away again.

And from then on, the night and the day were never without light.