Neo-Nazi

Neo-Nazis were groups which sought to revive the Nazi regime following its fall in Germany at the end of World War II.

20th century
In 1983, neo-Nazis firebombed the home of Ace's friend Manisha Purkayastha because she was from Pakistan. Thinking about this, Ace later lamented how Nazi ideologies had managed to survive beyond the Second World War. (PROSE: Illegal Alien, TV: Ghost Light)

In 1988, a neo-Nazi group led by Hans de Flores attempted to take control of the Nemesis statue and use it to establish a Fourth Reich, but they were foiled by the Seventh Doctor and Ace. De Flores and his group themselves were wiped out by the Isomorph Cybermen. (TV: Silver Nemesis)

21st century
In 2001, another neo-Nazi organisation, led by Adolf Hitler, Jr., pretending to be his father preserved by stolen Vvormak technology, planned to conquer the world with the help of demonic imps, but this plan was foiled by the Sixth Doctor and the Brigadier. (PROSE: The Shadow in the Glass)

Professor Jason Clearfield made contact with various neo-Nazi groups during his post-war quest to track down Die Glocke. He eventually found it around 2014, and also gained access to Nazi gold stockpiled by neo-Nazis to make his research financially viable. (PROSE: The Crawling Terror)

Later history
In 2593, on Tyler's Folly, Bernice Summerfield encountered the SSSSSSS ("Stella Stora Sigma Schutz-Staffel SturmSoldaten") which was considered the most ineffective Nazi group since the Outer Hebridean National Party. (PROSE: Down)