The poorly named Firstborn weren’t actually born. The Craeylu fabricated them in the Pool of Life. Each Firstborn was the first of their kind to awaken and very gifted. All were sorcerers and channelers (except the Harnae) and most were Earthmages too.
Upon rising from the Pool, the Firstborn floated to Sangrar from Heaven encased in what looked like giant soap bubbles. Along the way, the bubbles multiplied, like a child had waved a soapy wand, and each trailing bubble contained another of the Firstborn’s people. These were the Secondborn, who, like the Firstborn, weren’t really born at all.
The Secondborn landed on Sangrar, but far away from the Firstborn, who landed at Jahar, where the Ealar and Elehu were waiting for them. The Craeylu attended too, by means of a holographic projection trick from Finbardin’s grassy balcony in the Outermost Heavens. The gods came to prophecize, utter dire warnings and generally dampen the spirits of what would have otherwise been a most excellent day. Omens and foretellings usually aren’t a cause for celebration. More often than not, they predict doom of some sort and the First Congress of the Gods, as this grand meeting was later named, stayed true to form.
During the Congress, the Firstborn learned, mostly from Lillandra, that the eternally bright world upon which they’d landed would someday be plunged into darkness, that Sorrow would enter the world and try to rule them, that there were strict prohibitions as to whom they might love (in the physical sense only, they were free to give their hearts away to whomever they pleased, so long as they knew the rules on what could and couldn’t be consummated).
As channelers, the Firstborn all heard earthsong the moment they landed among the Stones and it delighted them, but they didn’t know what it meant until the gods explained the everything. By the end of the rather long-winded explanation, they knew that they had to pray and pray often to the Earth Mother, even though they didn’t understand what it meant to pray. Nonetheless, they nodded dutifully and then one of them asked for clarification.
Lillandra answered in great detail. As the goddess of fertility, it was right up her alley. A few cheeks turned red, including Nammoran’s – Kandol always described his grandfather as provincial in certain respects, by your standards he’d have felt quite comfortable in Victorian England – but most simply grinned until they looked around the Stones and realized how dire the situation was. There was only one of each race (ok, three Harnae, but I’m getting tired of excluding them). From what they’d just heard, praying worked much better with two than one. Only then, did the gods tell them about the Secondborn. Given the downers they’d just heard, I’m surprised some of them didn’t say to hell with it, but these Firstborn were made of stern stuff and knuckled down to the task at hand.
When the Congress came to an end, the Firstborn set off in search of their Secondborn. This took years, or decades, which really was rather ridiculous when you stop to think about it. Why would the gods make it so difficult for the Firstborn to find the Secondborn? All those years of searching and the seals trapping the Dark Lord kept weakening the entire time. The gods were playing with fire by hiding the Secondborn so well. Fortunately, there were just barely enough prayers to go around and keep One-Eye from escaping.
The only explanation I can come up with is that the gods were teaching the Firstborn adversity, to make them better appreciate the Secondborn when they found them, but I can’t imagine that would have been a problem. By the time the Firstborn stumbled across their Secondborn, they would have been starved for companionship and desire to pray with someone, anyone. Lastly, if it was a lesson on adversity the gods were after, wouldn’t it have been easier to throw a Troll or two their way, or if that wasn’t enough of a challenge, a Maldok or a Jixari?
The Firstborn found the Secondborn in reasonable numbers, at least a score or so, enough for each race to go forth and multiply (it went hand in hand with prayer) without too much inbreeding. Nammoran and Dar, however, found a whole gaggle of Secondborn, enough to form the Fair Folk tribes and the Forge Folk clans. Elves and Dwarves were always the most populous of the Elder Races, especially after the Reckoning.