Valyria

408 Years before Daenerys Targaryen was born and Aerys II Targaryen, the mad king, was murdered by one of his white robes. 22 years before the doom of Valyria.
They were closer to the gods than to men, so they all ascended.
Nothing could destroy valirian blood, except itself.
Bastards are bad omen. Dragons feared nothig, until she was born.