Title(s): banner-bearer and herald of Manwë
Parents: Eru Illuvatar (creator)
Chief among the Maiar of Valinor whose names are remembered in the histories of the Elder Days are Ilmarë, the handmaid of Varda, and Eönwë, the banner-bearer and herald of Manwë, whose might in arms is surpassed by none in Arda.
"Of the Maiar": Valaquenta: Silmarillion
On how he came into being:
In the beginning Eru, the One, who in the Elvish tongue is named Iluvatar, made the Ainur of his thought...
"Account of the Valar and Maiar according to the lore of the Eldar" Valaquenta: Silmarillion