Despite not being one of the classic Marvel characters created by the likes of Stan Lee, Steve Ditko, and Jack Kirby in the 1960s, Wolverine is still considered one of their best superheroes and is easily as big a fan-favourite as Spider-Man and The Avengers. It's not hard to see why that is either. The gruff X-Men character is like a comic book version of Clint Eastwood, and his adventures - which are usually much more violent than those of Captain America and Daredevil for example - have been keeping Marvel fans hooked for decades now. Whether it's in his classic blue and yellow costume, a vest and jeans, or any other variation worn since his first appearance in 1974, Wolverine is a Marvel mainstay. However, with a history which goes back as far as the 19th Century, there's a lot than even the most devoted fan may not know about this Canadian born clawed mutant. Wolverine has had a huge impact on the Marvel Universe and has been involved in any number of unique (and sometimes downright crazy) stories over the past forty years or so. Here, you will find just 20 of the most surprising facts about Wolverine. Whether it's the weird story behind his creation or how Hugh Jackman actually ended up being cast as the character on the big screen, these are sure to completely blow your mind.