Nurmengard

Nurmengard was the prison built by the Dark wizard Grindelwald during his reign of terror to hold his opponents. It is a colossal, jet-black fortress, in which the most important prisoners seemed to be held at the top. Whether the tower is heavily guarded or the higher rooms are simply made less accessible, the highest cells at least are not easy to reach; upon his arrival at Nurmengard, Voldemort had to invoke his unusual ability to fly in order to reach the topmost room [DH23]. Over the entrance to the prison was carved the slogan "For the Greater Good," a motto created by a young Albus Dumbledore when he and Grindelwald were friends plotting to overthrow the Statute of Secrecy and establish Wizarding dominance over Muggles. After Dumbledore defeated Grindelwald in 1945, the latter was sent to his own prison, locked in the topmost room of Nurmengard [DH18]. There, 53 years later, he was visited by Lord Voldemort, who was on the trail of the Elder Wand. Lying (out of remorse for his evil actions or otherwise) and claiming that he had never owned the wand, he infuriated Voldemort, who murdered him when the Death Eaters in Malfoy Manor summoned him after capturing Harry [DH23].

Nurmengard's history bears several similarities to the real-life Nazi regime. The name is similar to Nuremburg, the site of many pro-Nazi rallies [worldfuturefund.org]. The prison has words carved above the entrance, similar to the sign above the gate to the Nazi death camp Auschwitz that read, translated, "work makes freedom" [wsherc.org]. Lastly, both Grindelwald's and the Nazi regime were in power at the same time, before their respective downfalls in 1945.