The Dwarven Empire was once vast, and expanded as much underground as the Tevinter Imperium above. The dwarves do not know how the darkspawn came into existence; they just know that they appeared. The First Blight severely crippled the Dwarven Empire as Darkspawn flooded the Deep Roads that connected the thaigs and cities. Political disunity and inability to focus their defense led to the dwarves losing countless thaigs over the next couple of centuries, pushing the people to the brink of extinction. Orzammar closed its gates to any survivors, becoming the only bastion of dwarven culture. Centuries later, it was discovered that Kal-Sharok had also survived. However, they were bitter towards Orzammar, and refused to join with them. To this day, the dwarves continue to combat the darkspawn, and many surfacers are unaware of their plight.
All dwarves are born into castes that determine their job and how people treat them. It is possible to change castes, as dwarves inherit their caste from the parent of the same sex. If a woman had a son by a man of a higher caste, her son would be the same caste as his father, and the woman would also be raised up. If she bears a daughter, her daughter will take her caste. Becoming a Paragon also raises you to a different caste, though this is rare. Dwarves in Orzammar are obsessed with honour: their own, and that of their families. Everyone in the city is allied with someone, whether by blood or by word. The nobles do not engage directly in commerce themselves, as that is the domain of the Merchant Caste, but they do serve as patrons. They invest in shops or in artisans' work, and in turn reap a share of the profits as well as a measure of the credit. Merchants and warriors alike benefit from the service of a prestigious patron.
The Casteless are the descendants of criminals and other undesirables. Also, dwarves that leave for the surface are considered casteless. Many surface dwarves are merchants, leading to a misconception among surfacers that all or most dwarves are merchants. They are forced to wear tattoos -- known as brands -- to denote their status as Casteless. They are selected for only the most undesirable jobs. Some of the female casteless become Noble Hunters -- women who seek to raise their status by bearing a son to a dwarf of the Noble Caste. Most are reluctant to leave Orzammar, for fear that they will fall up into the sky and lose their Stone Sense.
The dwarves don’t have an official religion. They do not believe in gods. Instead, their philosophy promotes excellence, and an almost intimate tie to the rock -- the Stone -- that houses them. They speak of it as if it is alive. They respect, fear, cherish, and give thanks to her for protecting them and providing them with her bounty. Worship is revered for the Ancestors, the dwarves that have been raised to Paragon status for great achievements. Dwarves believe that when they die, they return to the stone. In death, it is said the Paragons are said to become one with the densest stone at the base of all mountains -- a foundation upon which all dwarven society rests.