Grindelwald (? - 1945?)
The dark wizard that Dumbledore defeated in 1945 (PS6, PS13).
Because of the year of Grindelwald's defeat, which is stated on the Chocolate Frog card about Dumbledore, some have speculated that Grindelwald and Hitler were the same person or that Grindelwald was somehow related to the events of World War II. Rowling has confirmed that Grindelwald is deceased (TLC).
'Grindelwald' is a small village in Switzerland; JK pronounces Grindelwald's name “GRIN dell vald” (TLC). The name could also refer to Grendel, the troll-like monster of the Anglo-Saxon epic Beowulf.