Slaves were used for everything from construction work to caring for children. Rome, like the entire ancient world was a slave based society. The ancients considered their slaves as their extra arms, and sometimes as their eyes and ears if they needed information.
Slaves
The emperor Caracalla extended Roman citizenship to all the freeborn in the empire in 212 AD.
the roman empire started because instead of killing the people they sold them to be slaves
No, the slaves had a really hard time.
They were slaves and prosecuted.
Freedmen were slaves who were freed by their masters. They did not actually from a social class as such. They were former slaves.
No it did not. Slaves in antiquity were war captives. After the end of Rome's wars of expansion the supply of slaves dried up.
Spartacus died by a Roman senator called Crassus, He crucified Spartacus along with 6000 other slaves. This was to warn slaves not to try and destroy the Roman Empire. Hope this helps :)
The slaves within the boundaries of the Roman empire had the same religion as the Roman citizens. Slavery was a social class, and the lowest on the ladder. Therefore, being a social class, they would have been influenced culturally the same way as citizens. Slaves were not citizens, but followed what the citizens did. The religion of the Roman empire was paganism, therefore the slaves were as well pagans. The only exception would be people from distant lands who were captured and forced to be slaves; in Asia Minor there would have been Christians and Jews, and those religions spread to the Roman empire; people of all social standings--from slaves to aristocrats--would have converted. But, basically, what I'm trying to say, is that the slaves themselves did not have their own religion.
They were defeated armies drafted as slaves to the Roman Empire.
It was not built is is a country and it has been there since the fall of the roman empire who had used them as slaves.
Unknown, but perhaps 20% or double the average for the Roman Empire as a whole.