Nurmengard Castle

Nurmengard was a wizarding prison, originally built by Gellert Grindelwald to hold his opponents, but ultimately served to imprison Grindelwald after his defeat in 1945 until his death in 1998.

Creation
The prison was built on the orders of the Dark Wizard Gellert Grindelwald in order to hold his opponents. Grindelwald's slogan "For the Greater Good" was carved over the prison's entrance. After a number of years terrorising Europe, Grindelwald was confronted and defeated by his former best friend, Albus Dumbledore.

Grindelwald's imprisonment
Grindelwald was imprisoned in the top-most cell in the highest tower inside Nurmengard after his defeat by Albus Dumbledore. His cell had a small window, too narrow for a man to leave or enter, a hard bed, and a thin blanket. It is unknown if there were any other prisoners ever held at Nurmengard, but around the time of Grindelwald's death, it is likely that he was the only prisoner present as the past inmates were likely incarcerated there at Grindelwald's behest. Grindelwald was certainly fed and kept alive for fifty-three years, so there was at least a supply of food and someone (or something) bringing it to him, although he was emaciated, frail and missing teeth.

Quest for the Elder Wand
In his quest for the Elder Wand, Lord Voldemort travelled to Nurmengard in 1998, using his skills of flight and possibly human transfiguration to break into Grindelwald's cell. After confronting him for information on the Wand's location, Voldemort killed Grindelwald and then flew away. The ultimate fate of the prison is unknown.

Description
Nurmengard was a gigantic, towering building made of black rock and with high walls, that is described as "jet-black," "forbidding," and a "grim fortress." The cell that was inhabited by Gellert Grindelwald since 1945 had been a dark and ominous room in the highest tower, with a hard bed and a ragged, thin blanket.

Behind the scenes

 * Nurmengard may be a reference to, the city in Germany that was the site of many important rallies, as well as was also the place where the anti-Jewish  were promulgated. Later the city was famous as the site of the prison used to hold infamous Nazi war criminals, as well as the Nuremberg Trials where they were tried for war crimes and crimes against humanity. Likewise, Nurmengard was created as a monument to Grindelwald's oppressive regime, but later became a symbol of his downfall.
 * The suffix "-gard" comes from the Norse "gard," meaning "enclosure" or "walled town." Also, in French, "garder" means "to keep, ward, guard, save, preserve".
 * J.R.R. Tolkien used a similar word for his place names in Middle-earth when referring to enclosed spaces: for instance, the fortress of the dark wizard Saruman is named Isengard meaning literally "iron fortress." Isengard was built by the people of Numenor, so the first two syllables of Numenor and the last one of Isengard would be Numengard. It is possible that J.K. Rowling did not read Tolkien's Legendarium, written a few decades ago, but it is more likely that the 'gard' part was more of a coincedence than 'Numen.'
 * "The greater good" is an essential idea of the utilitarian philosophy. "For The Greater Good" may also be a reference to "" (German, "Work makes [one] free" or "Work liberates") the motto that was mendaciously inscribed over the entrance gates to several (The exact wording of the inscription at Nurmengard is unknown, since Grindelwald's exact nationality or his language of preference, are not specified in the books: the German translation of his slogan would be "Für das höhere Wohl", although the official German translation in the book reads "für das größere Wohl").
 * In, Nurmengard appears as a large and shadowy building on a mountainside with a tall roof and multiple cell windows. It also appears to be far larger than Azkaban. If theory about the relation to Nuremberg is correct, then the closest mountains from there is the German side of Bayerischer Wald or Oberpfälzer Wald.

Notes and references
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