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[Harry Potter]Are there dementors outside of Azkaban?

Just watching the Order of the Phoenix, during Harry's trial Umbridge claims that dementors are under the control of the Ministry. Are there international dementors in the wild? Do they sometimes cross the border to the UK and get shipped to Azkaban? Are they in Azkaban against their will?
gpt
>Just watching the Order of the Phoenix, during Harry's trial Umbridge claims that dementors are under the control of the Ministry. Are there international dementors in the wild? Do they sometimes cross the border to the UK and get shipped to Azkaban? Are they in Azkaban against their will?

They are under the control of the Ministry to some extent. It's more of a contract so to speak, in that the Dementors native to the island of Azkaban are willing to guard magical prisoners for the Ministry in exchange for feasting on their happiness and souls. It's why they then rebelled to join Voldemort later on, as Voldy offered them many more (and happier) victims to feed on. 

To this extent, they're only really found on their native island of Azkaban and in Ministry locations (like in the Ministry of Magic as guards). Some may have migrated to other locations around the world for unrestricted access to prey, but more likely they'll remain near Ministry facilities. Well, up until the death of Voldemort. By this point the Ministry has regained control of the magical world, and has disbanded the Dementor alliance due to their ties to the Death Eaters. Now Aurors patrol Azkaban, and the Dementors were exiled elsewhere. 

It's suggested that the Dementors came into existence when the original master of Azkaban Ekrizdis created it and lured Muggles there for torturing. Either he created the Dementors to aid in his dark and chilling exploits, or they flocked to the location to revel in sucking the remaining happiness from the Muggles. The Ministry later came over and considered destroying the place due to its foul nature, but withheld this decision due to suspected reprisals from Dementors. They then stuck their prisoners there and used the native Dementors for guards in exchange for allowing them to feast on inmates.