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Harry Potter - 10 facts you probably don’t know about Sirius Black

He's definitely one of the best Harry Potter characters, even in dog form, so let's learn some Sirius Black facts and delve into the life of Harry's godfather.

Harry Potter - Sirius Black facts

What are 10 facts you didn’t know about Sirius Black? In the wake of Harry’s dad’s death, there was a void in his life for a father figure. Vernon Dursley was never going to fill that, after all. While the likes of Hagrid and Dumbledore occupy different facets of the role, it’s Sirius Black who became the closest.

After all, Sirius is godfather to Harry Potter and was his dad’s best friend. Of all the best Harry Potter characters, Sirius is the nearest thing Harry has to family. When you’re watching the Harry Potter movies in order, it’s impossible not to feel the emotional heft of their bond, conveyed beautifully by Harry Potter cast members Daniel Radcliffe and Gary Oldman.

So we’ve established that Sirius is very significant throughout the best movies in this franchise, even though he’s only in a few of them. Let’s go through some Sirius Black facts and learn a bit more about the escaped prisoner they sometimes call Padfoot.

10. His name is a massive spoiler

We all know that the Harry Potter author loves taking names from various languages and the world around her. Well, one of the most obvious examples of this is that Sirius is from astronomy.

Sirius is the brightest star in the sky, also known as the Dog Star, in the constellation Canis Major, also known as the Great Dog. Gee, wonder who that giant dog in Prisoner of Azkaban could be?

Sirius Black in his dog form in Harry Potter and the Prisoner of Azkaban

9. He cameos elsewhere in the author’s work

In the BBC miniseries The Casual Vacancy, based on one of the Potter author’s other novels, there’s a comment on the parish council’s death announcement by “S. Black”. We see you, Sirius!

8. His Animagus form was very specifically chosen

Sirius and his best friend James Potter both chose large Animagus forms in order to be able to help control their other friend, Remus Lupin, during his werewolf transformations.

But more than that, Sirius perfectly fits a dog. He’s loyal and friendly to those he cares for, but capable of being fierce and aggressive to those who threaten his kin. Just like man’s best friend in that sense.

7. He might have been Robson Green

Apparently, Robson Green was in the frame to play Sirius, before Alfonso Cuaron stepped in to direct Prisoner of Azkaban. Predominantly a British TV actor – Waterloo Road fans, make yourself known – this would have been a major break for him in Hollywood, just like his old musical buddy Jerome Flynn managed as Bronn in Game of Thrones.

Harry Potter - Robson Green nearly played Sirius Black

6. He’s the subject of a lost story

In 2008, the Harry Potter author wrote a handwritten short story for a charity auction, choosing to tell the tale of Sirius Black and James Potter encountering some Muggle policemen.

It sold for £25,000 but was stolen in 2017. The author urged people not to buy the story, which has not been made available legitimately, if they were offered the chance.

5. He almost formed a strange but cute friendship with a dog lover

We all know that Sirius went on the run after the Time Turner shenanigans at the end of Prisoner of Azkaban. But in an early draft of the next novel, Goblet of Fire. Sirius found his dog form being cared for by an eccentric witch called Mopsy. She looked after and fed Sirius, along with her other canine companions.

Given the serious stuff going on in Goblet of Fire and Sirius’s role as an adviser from a distance for the central trio, we’re quite glad this unusual plot thread got ditched.

Harry Potter - Gary Oldman as Sirius Black

4. He might be a video game reference

Sirius and his brother Regulus both turn out to be good guys in the Potter story, despite their inauspicious introductions. As it turns out, both character names also appear in the late-’90s Nintendo game Bomberman 64.

Sirius is a warrior who assists the player, while Regulus is a space pirate. We don’t know if these shared names were a deliberate nod, but it’s a fun, constellation-based coincidence if not.

3. He should have been even bigger as a dog

In the Harry Potter books, Sirius’s dog form is described as being similar in size to a bear – grizzly or polar presumably, rather than Paddington.

This didn’t carry over into the movies, where his Animagus form is more akin to a large domestic dog than an enormous, quasi-ursine monster. It certainly would’ve made him more of a physical match for Lupin after his werewolf transformation.

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2. He’s part of the most popular Harry Potter ship

Having spent our share of time in fanfic communities during the 2000s, we were surprised to learn that Drarry – the romance between Draco Malfoy and Harry Potter – didn’t produce the most stories in 2023. Instead, the most popular Harry Potter ship on fanfic site Archive of Our Own is now Wolfstar – Sirius and Lupin.

Given their close bond on both page and screen, it’s understandable that they’re a popular ship, but we were surprised that they’ve usurped Drarry.

1. He really did laugh when he was arrested, even though he was innocent

One of the most damning details of the case against Sirius Black was that he was found laughing after apparently selling out the Potters and murdering Peter Pettigrew. The Potter author has revealed that this detail of the story was true, but that there was a reason behind it.

In a 2005 interview with The Leaky Cauldron, she said that it was “a humorless laugh” born of grief at the loss of his friends and derision at realizing that Pettigrew was “better at hiding secrets than they knew”. Look, we were shocked by Pettigrew’s slimy smarts too.

Gary Oldman as Sirius Black and Daniel Radcliffe as Harry Potter in Order of the Phoenix

For more tidbits of fascinating information from the Wizarding World, take a look at our guides to Voldemort, Dumbledore, Luna Lovegood, Ron Weasley, and Hagrid. We’ve also explained why the most heart-breaking Harry Potter scene didn’t make the movies and why this Harry Potter monster was too terrifying for the big screen.

Elsewhere, find out why we can’t forgive the Harry Potter finale and look ahead to new movies, including the Fantastic Beasts 4 release date and the possible Harry Potter and the Cursed Child release date. We’ve also got all of the info on the Harry Potter TV series release date.

The creator of the Harry Potter series, JK Rowling, has made a number of transphobic remarks on social media in recent years. If you’d like to learn more about transgender equality or lend your support, here are two charities we encourage you to visit: the National Center for Transgender Equality in the US and Mermaids in the UK.