First page updated adding here for ease of access. These are very old gods, reaching back to the very dawn of humanity but as can be seen in their tenets they had adapted to fit an agrarian warlike tribal society, hence their conflict with the Old Gods and ultimate fading from the world, though it does not seem to have been complete
Father Sky
The Storm God, Victory Bringer, Father of Battles
Alignment: True Neutral
Domains: Storm, War, Nobility
Known Supernatural Servitors: Air Elementals, Thunderbirds
The Church: When the First Men first came to Westeros ranging across the Arm of Dorne it was the war priests of the Father sky who drove them forward, the sound of their great aurochs hide drums as the call of thunder. His were the berserkers who drove themselves into mad fervor that they might wrestle giants down and slay them, but to him gave honor also the cunning chief and sage who would see far for all that is lies under the heavens bright.
Tenets of the Faith: From what Waymar can gleam of his dreams the Strom God whose daughter was Elenei and whose wrath only the Builder's works could turn aside bid his followers to be as he was fierce and savage in war, fair and even-handed in peace to kith and kin. Of course not all men agreed with the god's notion of fairness, but such has been the nature of men and gods since time's beginning.
Worshipers by Region: None known (Ceria Strom and Ysilla Royce have both received visitations and power likely originating from him)
Infrastructure: None known (Former range throughout Westeros, most recent temples likely on the three Sisters, ancient center of worship in the Stormlands)
Mother Earth
The Hearth Keeper, The Bountiful One, Earthshaker
Alignment: True Neutral
Domains: Cavern, Family, Earth
Known Supernatural Servitors: Earth Elementals, Thunderbirds
The Church: Little enough to you know of those who kept the fire burning in those long vanished holds of the First Men for none in your company hears an echo of their dreams. You know they were the keepers of ancient tales they they loved not war and the shedding of blood and were slow indeed to rise to anger but that even the fiercest chieftain would not lightly provoke them, for like the twisting of the earth their wrath could bring untold ruin.
Tenets of the Faith: The act of cultivating the land and of cooking food thus obtained seemed to have been both sacred to Mother Earth and thus among the greatest sin one could commit in her eyes was leaving land to lie fallow once it had been claimed to the plow second only to disturbing the rest of the dead.
Worshipers by Region: None known
Infrastructure: None known (Former range throughout Westeros, most recent temples likely on the Three Sisters, ancient center of worship in the Westerlands)