The campaign is set in the land called Varisia, a largely untamed land built over the ancient ruins of a long-lost civilization called Thassilon. There are ruins of the old civilation all over the place, so there is a strong anthropology/archeology element to the campaign. There are three city-states which provide various forms and degrees of stability for the region. Korvosa is a decadent would-be kingdom strongly influenced by the collapsing empire of Cheliax, located to the south. Magnimar is a more independent-minded city-state and nearest to the campaign starting point. Riddleport is a nearly lawless city of thieves about 500 miles North along the coast. Most of the city-dwelling humans are part or full Chelaxian. Other human races include the gypsy-like Varisians and tribal Shoanti.
The characters will be starting in the town of Sandpoint on the West coast of Varisia. Sandpoint is a small town (Population 1,240) with some surprisingly large-town features. The campaign begins with Sandpoint’s Swallowtail Festival on the first day of Autumn. This year’s festival promises to be an exceptionally joyous one as the town is dedicating their newly built temple. The new temple replaces one which burned to the ground five years ago, killing the town priest and his adopted aasimar daughter in the process. This town will be the home base for the first few adventures, so the PCs will get to know it and its prominent citizens well.
The following is copied directly from the Introduction of Rise of the Runelords; Burnt Offerings adventure module.
Sandpoint, in a nutshell, is your PCs’ new hometown. Here, they’ll make friends, buy their first suit of armor, visit their first tavern, and eventually tangle with monsters. It’s the start of a brand-new campaign, one set in the equally brand-new world of Golarion, the setting for the Pathfinder Chronicles Campaign Setting. The adventures your PCs are about to embark on will determine the fate of not just Sandpoint, but the surrounding region of Varisia as well. If they fail, their friends and countrymen might well be doomed to a new age of slavery and horror, but if they succeed, their triumphs shall be recorded by sages and kings, their immortality assured.
For much of written history, world events followed charted routes. Oracles and seers mapped out the future in the stars above, and their prophecies always gave a reliable view of the ages to come. Until a god died a century ago. No one saw that coming, and now, the old prophecies are failing. Oracles go mad and seers desperately try to account for the loss of the future. While some cry out that the world is at an end, they’ve been doing so for 100 years now. And the world’s still here. It’s just unclear where things are going. The future of Golarion is open, ready to receive the triumphs and failures of a new generation of heroes.