How I Met Your Mother was a hit show by almost any standard, so it's no surprise to hear that fans have taken the time to learn as much as possible about each and every one of the characters of the series. After all, they're all so unique and dynamic, who wouldn't want to know more about them?

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Marshall is one of the leading characters of the show, being Ted Mosby's best friend (no offense to Barney). That makes him fairly important, but there's still so much we could learn about his character. Marshall may seem like a fun and easy-going guy (and for the most part he totally is), but there is some hidden depth to be found. Well, sort of hidden depth. This is a character who runs very close to the surface.

Based On A Real Person

Marshall looking at his hand in How I Met Your Mother.

Did you know that Marshall Erikson is actually based on a real person? He was based on the series writer Craig Thomas.

Another fun note for fans to be aware of: Craig Thomas' wife, Rebecca Alson-Milkman, was the inspiration for Marshall's wife, Lily. So it's no wonder that these two ended up having so much chemistry on screen. They're based on a real-life couple!

Some Very Strange Quirks

Marshall is a character full of odd and memorable quirks. Given that he frequently provided the role of comic relief, this actually makes a lot of sense. That being said, some of Marshall's quirks were funnier or stranger than others.

For example, he's a member of a Funk band, and he's completely and utterly obsessed with games. Perhaps too much, according to Marshall's friends. He's also impossible to beat at Zitch Dog – seriously, don't challenge him to a game, you'll just hate yourself (and him) by the end. Oh! And he can telepathically communicate with his wife, Lily. Or at least, he can in public, and it seems to require eye-contact.

A Man of Many Names

Marshall Eriksen is a character who collected dozens of nicknames over the course of the show. Given how many antics he got up to, this probably isn't a surprise for most fans.

During the series, he collected the following nicknames and titles: Marshmallow, The Kid, Fudge Supreme, Judge Fudge, Mr. Awesome, Ghost in the Post, Sports Guy, Funny Butt, Vanilla Thunder, Marsh Madness, Papa, and Beercules. And some of those are going to be so much fun to explain to his children someday.

A Fan of Many

Over the course of How I Met Your Mother, fans were forced to learn that Marshall is a huge fan of sports. And he favors certain teams over others, obviously. What is interesting is that Marshall is convinced into liking other teams over the long series.

Marshall is an avid fan of the Minnesota Vikings, as well as the Minnesota Twins. He also may even be a fan of the New York Mets, but that point is contested.

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Played By Three Actors

Marshall Eriksen's character is portrayed by three different actors, thanks to all of the flashbacks the series has to offer. Adult Marshall is played by the one and only Jason Segel, and as such that's the most commonly known and pictured version of Marshall.

College-age Marshall was also played by Segel. But we've also seen Marshall at two different ages that required different actors to step in. Tyler Peterson stepped in to play the ten-year-old version of Marshall – the Marshall that was obsessed with living among the Gorillas and making the world a better place for them. He reprised the role of thirteen-year-old Marshall and is the version responsible for Marshall getting into smoking. And then there's eight-year-old Marshall, who was played by Koby Rouviere.

The One And Only

Ted and Marshal sitting in rain

While Ted and Barney both dated their way through a massive number of women, Marshall only ever had one serious relationship in the series, Lily Aldrin. He did make an attempt at dating after she dumped him, but the most he ever got was a few dates with one woman (who notably had 'crazy eyes').

Lily is the only character that Marshall has ever been with, sexually speaking. And she's the one he references whenever he tries to play the 'have you ever' game, which tends to make Lily angry.

A Very Caring Individual

Marshall, Ted, and Lily hugging in How I Met Your Mother.

Marshall is quite possibly the most caring and compassionate character in the series. He's willing to go out of his way to help everyone and anyone.

On several occasions, we've caught him trying to help somebody in need, be it a dominate plot or a background reference. For example, during The Goat, Marshall can be heard trying to talk Lily into letting his uncle move in with them (his uncle, who apparently is in the Duluth Mental Hospital, and presumably needs a lot of help and care).

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Some Issues In the Hair Department

how-i-met-your-mother-marshall

Where Marshall's compassion is boundless, the same cannot be said about his hair. In fact, Marshall has quite a bit of trouble in the hair department. For one thing, we know that he is literally incapable of growing a mustache (according to Robin).

He also starts losing his hair at a relatively young age, due to all the stress he's been put through with trying to save the environment. The Marshall of the future is one who has a rapidly receding hairline, though he does a decent job of pulling off the look.

The Actor and the Character Have Something In Common

Jason Segel is the actor behind Marshall Eriksen, and there's a lot of interesting tidbits to know about his on-screen brothers. Marshall is the youngest of his brothers, yet Segel is actually the same age as one of his on-screen brothers (Robert Michael Ryan/Marvin Jr.) and is but a year older than the other one (Ned Rolsma/Marcus).

Additionally, Marshall is constantly portrayed as the shortest brother in the family. Which is impressive, given how tall he is compared to the main characters. And that's a fact that is true in real life as well! Jason Segel is shorter than both Ned Rolsma and Robert Michael Ryan.

He Got His Wish

Marshall's character wanted a big family ever since he was a little boy. And it's something of a point of contention between him and his wife, as Lily seemed content not to have any more children after the first one.

But then towards the end of the series, they announced that she was pregnant once again. And then later she even had a third child with Marshall. And that proves that for the most part, Marshall did get his wish in the end.

NEXT: How I Met Your Mother: 10 Behind The Scenes Facts You Didn't Know