Imagine a city captured and recaptured over the centuries, taken from empire to evil overlord to city state time and time again. Rich and convoluted history, myth and legend surround the city, its many temples and artifacts. The people of this prosperous, strategically valuable land are used to changes and corruption in government, but something new is afoot…
Your adventuring group returns to the city to find that everything has changed yet nothing has. No one recognizes you, no one trusts you, and every serf seems subtly paranoid. Construction on the new city center has stopped and the scaffolds stand skeletal and empty, chilled by snow in the winter air…

Take a look at thewiki. There is some more helpful info there.

The Sihelburg Situation