So the basic story is that Argrath was exiled to Prax as a youth. He was taken as a slave by the Bison Tribe, but while a slave he found/freed the White Bull spirit. The White Bull is a son of Storm Bull/brother of Waha who the Praxians believe will lead them to fight a final battle against Gbaji or Chaos or whatever.
Argrath, as the person in direct contact with the White Bull, becomes the leader of this new magical society, which thanks to the Lunars spreads quickly within all the Praxian tribes.
But meanwhile, Argrath is part of the Sartar Dynasty (from a minor branch, but thanks to the Lunars that’s really all there is) and is an Orlanth Adventurous cultist. He is an experimental heroquester (where do you think he found the White Bull?) and is seeking things in the weird recesses of the Hero Plane – the Drinking Giant’s Cauldron, the Dragonteeth, etc. When a baby giant is born as an unexpected side effect of one of these quests, Argrath protects her on her voyage to the sea. This brings him into contact with Harrek the Berserk.
After a rocky start, Harrek and Argrath become allies and they circumnavigate around the Homeward Ocean, plundering and adventuring, and seeing all sorts of things. Teshnite sun priests, Teleosites, bat-hsunchen in Laskal, Doraddi, Fonritian Ompalam cultists, the ruins of Jrustela, Seshengi sorcerers, and so much more. By the time Argrath gets to the Holy Country, he is one of the most broadly adventured people in Glorantha.
From the Holy Country, Argrath returns to Prax where the White Bull movement has spread during his absence. He gathers members from all the tribes and summons Jaldon Goldentooth so that he can conquer (liberate) New Pavis from the Lunars. After that he quickly unrolls the Lunar garrisons in the River of Cradles.
Shortly after, he gets his first major set-back. Argrath tries to conquer Dragon Pass with his Praxian allies, but is beaten by the Lunar College of Magic at Hender’s Ruins. He returns to New Pavis to recoup, but in the meanwhile the Dragonrise happens and Kallyr Starbrow is acclaimed Prince of Sartar.
That gets us to about the starting date of RQG.
Now the more interesting story is what comes next. Kallyr’s rule of Sartar is short-lived and Argrath returns to Dragon Pass with an army of Praxians and adventurers. After forcing the Lunars out of Alda-Chur, Argrath marches on Boldhome and is acclaimed Prince of Sartar. He has little direct relationship with the traditional Sartarite leaders – the tribes and the city councils, but he is backed by Orlanth Adventurous, Storm Bull, tricksters, an army of Praxians, plenty of misfits, adventurers, outlaws, hedge priests, shamans, and weirdos – basically everything that Thunder Rebels says isn’t there. Its clear that the new Prince with a seasoned army (and plenty of cavalry) plans to strike against the Lunar Empire, but first he needs to get his ducks in a row, so to speak. But the clock is ticking as the Red Emperor and Jar-eel have suppressed the revolt in the Redlands, and are restoring order to the Lunar Provinces.
That’s the scene in 1627 when the ball really starts rolling. At that point we are in the White Bear and Red Moon board game.
And meanwhile, Argrath is building his own “secret weapon”- a Sartar Magical Union intended to be able to take on the Lunar College of Magic