Hell

God made Hell as the realm for punishment and pain of the afterlife. Human souls who are sent to Hell are tormented until their humanity is stripped away and they become Demons.

Hierarchy and Denizens
Alliances and affiliations in Hell exist but they tend not to last for long periods. Hell's hierarchy exists, but is not as rigid and controlled as Heaven's. Tammi was a demonic witch who appeared to be above average demons. Alastair was Hell's grand torturer.

Human souls can get sent to Hell after making deals with Crossroads Demons or other demons. Hellhounds capture then kill the person when their their time is up. See Deals and Pacts for information on characters who have made demonic deals.

The King of Hell
Lucifer ruled Hell from his cage after Michael cast him from Heaven under God's orders. Azazel describes his rule of Hell as "been there, done that", and is further called a "tyrant" by Casey, making him a prominent king of hell. Crowley usurped the throne after Lucifer was re-imprisoned, proclaiming himself as the King of Hell.

History
Dean Winchester spent four months in Earth time in hell, but he reported that time passed differently there, and for him it was more like forty years. This made 3 days on Earth roughly equivelant to a year in Hell. Lucifer was the ruler of Hell, and has millions of demons under his command. Hell was created by God, and Lucifer was thrown into hell by the Archangel Michael.

God sent Castiel to pull Dean out of Hell, in doing this Castiel left his mark on Dean's arm. According to Azazel, Lilith did spend some time in the "pit" (in other words, Hell). Alastair first met Dean Winchester while he was in Hell. It has been hinted that Azazel is Hell's viceroy in the absence of Lucifer. Lucifer was bound in a special part of Hell that could only be accessed from a single gateway, located beneath St. Mary's Convent in Ilchester, Maryland.

In The Man Who Would Be King, Crowley, now the king of Hell, changed Hell to an never ending line-up. It was also revealed that Castiel pulled Sam pull from the pit, but unintentionally forgot Sam's soul, thus plaguing him with memories from hell.