The following events occurred in the 1940s:
- 1940: Rubeus Hagrid starts at Hogwarts.
- 1940 to 1945: Grindelwald's Revolution.
- 1943: Tom Riddle opens the Chamber of Secrets. Several students are injured, and Moaning Myrtle is killed by the Basilisk. Hagrid is framed for the attacks by Riddle and is expelled. With the murder of Moaning Myrtle, Tom Riddle transforms his diary into his first horcrux.
- Summer, 1943: Tom Riddle murders his father, Tom Riddle Sr., and his grandparents, Thomas and Mary Riddle, for the abandoning of his late mother, Merope Gaunt. His uncle, Morfin Gaunt is framed for the attacks by Riddle and is sent to Azkaban.  With the murder of the Riddles, Tom Riddle transforms Marvolo Gaunt's Ring into his second horcrux.
- 1944: Margot Droope receives an award at Hogwarts School of Witchcraft and Wizardry for unknown reasons.
- 1945: Tom Riddle graduates from Hogwarts School of Witchcraft and Wizardry.
- 1945: Albus Dumbledore defeats Gellert Grindelwald, who is sentenced to life in Nurmengard.
- 1946: Tom Riddle murders Hepzibah Smith, stealing artefacts of Helga Hufflepuff and Salazar Slytherin 
- 1946: The seventy-eighth Wizarding Schools Potions Championship is held.
- 1947: The Werewolf Register is introduced.
- 1947: A History of Magic by Bathilda Bagshot is first published.
- A fanged gerbil was found to have been put into Augusta Longbottom's handbag as a joke by her husband.
- 1 September, 1947: Minerva McGonagall starts attending Hogwarts School of Witchcraft and Wizardry, and proves to be a Hatstall during her Sorting.
- 1948: Wilhelmina Tuft becomes Minister for Magic.
- 1949: A hippocampus is caught by Merpeople off the coast of Scotland.
- 1940 to 1944: Winky Crockett captained the Slytherin Quidditch team.
- 1944 to 1948: Neil Lament captained the Slytherin Quidditch team.
- 1948: Andrew Snowyowl captained the Slytherin Quidditch team from 1948 until the end of the decade.
- 1940: Fabius Watkins
- 15 May, 1941 or 1931: Pomona Sprout
- 1945: Devlin Whitehorn
- 1946: Broderick Bode
- 1947: Laurentia Fletwock
- 1942: Stephen Hawking
- 1941: Karl Broadmoor
- 1949: Unidentified Minister of Magical Transportation
- 30 October 1949: Molly Prewett
- 1940: Mr. Hagrid
- 1942: Eunice Murray
- 1943: Cygnus Black II
- 13 June, 1943: Myrtle Warren
- Summer, 1943: Tom Riddle Sr.
- Summer, 1943: Thomas Riddle
- Summer, 1943: Mary Riddle
- c. 1946: Hepzibah Smith
Behind the scenes
- 1940 Michael Gambon who plays Professor Albus Dumbledore was born on 19 October
- 1940 John Hurt who plays Mr. Ollivander was born on 22 January
- 1942: Mike Newell, director of the film adaptation of Harry Potter and the Goblet of Fire, was born on 28 March.
- 1942: Gemma Jones, who plays Hogwarts' Nurse Poppy Pomfrey, was born on 4 December.
- 1945: Andrew Burt, a British actor who provided voices in the video game adaptation of Harry Potter and the Deathly Hallows: Part 1, was born on 23 May.
- 1946: Alan Rickman, the actor who portrays Severus Snape, was born on 21 February died on the 14 January 2016
- According to the mini-adventure The Queen's Handbag, Augusta Longbottom, grandmother of Neville Longbottom, was the victim of a prank by her husband involving her handbag and a fanged gerbil in 1947, leading her to booby-trap her handbags from then on (leading to some pain for Ron Weasley). The Queen's Handbag breaks from canon in several places (not least of which by being set in 2006), so therefore whether anything included in the adventure actually counts as continuity is a matter of debate. This piece of information regarding Longbottom is listed here, however, as the only piece of new Potter Universe backstory offered in the mini-adventure.
- 1947 Richard Griffiths who plays who plays Vernon Dursley is born on the 31 July died on the 28 March 2008
- 1949 Bill Nighy who plays who plays Rufus Scrimgeour is on the 19 Decemcber
- 1949 George Harris who plays Kingsley Shacklebolt is born on the 20 October
- 1949 Jim Broadbent who plays Horace Slughorn is born on the 24 May
Notes and references
- ↑ Harry Potter and the Chamber of Secrets
- ↑ Wonderbook: Book of Potions
- ↑ Fantastic Beasts and Where to Find Them (real) - Chapter 1 (About the Author)
- ↑ Fantastic Beasts and Where to Find Them (real) - Chapter 3 (A Brief History of Muggle Awareness of Fantastic Beasts)
- ↑ Pottermore - New from J.K. Rowling: "Ministers for Magic"
- ↑ Quidditch Through the Ages (real) - Chapter Nine (The Development of the Racing Broom)
- ↑ 7.0 7.1 7.2 Harry Potter: The Exhibition, (see this image)
- ↑ Mugglenet — Birthday archive: Pomona Sprout (information retrieved from J.K. Rowling's Official Site)
- ↑ Pottermore biography of Minerva McGonagall (transcription available here)
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