The period drama Mad Men aired for seven seasons on AMC from 2007to 2015 and introduced viewers to the world of 1960s advertising. It featured a star-studded cast that included Jon Hamm, Elisabeth Moss (The Handmaid’s Tale), January Jones, Christina Hendricks, Jared Harris (Chernobyl), and John Slattery, among others.

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Each character had their own storied past and fascinating storylines from season to season, sometimes with bits and pieces revealed as the series progressed.

But even so, there are some hidden details you might have missed about the main characters, most of whom worked at the fictional Sterling Cooper advertising agency.

Don’s Womanizing Ways Stemmed From His Unhappy Upbringing

Jon Hamm as Don Draper in Mad Men

Any fan of the show knows that Don Draper isn’t really Don Draper, but rather a man named Dick Whitman who assumed the identity of his Lieutenant after he died during military service. But why was Dick so enthusiastic to live life as someone else? Because his own upbringing was a sad tale.

Born to a prostitute who died in childbirth and a drunk who died when he was a kid, Dick was left to live with his stepmother who had no issues constantly reminding him where he came from. Though it’s no excuse, this sheds some light on why Don had such a vile attitude towards women and relationships, and had problems committing.

Roger Met Don in a Fur Coat Shop

It’s easy to forget how Don actually came to work at Sterling Cooper, especially without any prior advertising experience. Roger, the son of the company’s co-founder, was shopping for fur coats when he ran into Don, who was working at the specialty shop as a salesman. When Roger complimented the advertisement for the store, Don revealed that it was he who created it. This impressed Roger, while Don, upon receiving Roger’s business card and seeing who he was, sent a portfolio of his work along with the fur coat Roger purchased (for Joan!)

Later, Don strategically placed himself in the lobby of Sterling Cooper where he “accidentally” bumped into Roger. They went for drinks, Don put on the charm (while the drinks flowed freely) and well, the rest is history.

Joan Was Married Before

Joan and Roger embracing in Mad Men

Little is known about Joan’s upbringing, aside from the fact that she was raised by her mother who may have had a drinking problem. And while we know she had an ongoing, on and off affair with Roger, and eventually married and divorced Greg, she confessed at one point that she had been divorced twice.

Who was her first husband? That’s unclear. But she also had two abortions prior to finally giving birth to her son Kevin. So there’s a lot we never really knew about the mysterious Joan's past.

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Don Draper Was Based On A Real Person

Don Draper sitting at desk in Mad Men

It’s hard to imagine that someone as dapper, charming, and smart could exist in real life. And while the man who the character of Don Draper was based on might share some vaguely similar qualities, he did indeed serve as the inspiration.

Draper Daniels was an ad man from Chicago who is credited with creating the widely popular Marlboro Man ad campaign. Considered to be one of the best copy guys of his time, Don Draper was based, at least in part, on this legend of the advertising industry.

The Man Who Played Freddy Rumsen is Bill Murray’s Brother

Freddy looking serious on Mad Men

This detail might not necessarily have been hidden as much as many people probably didn’t even know about it. The character of Freddy Rumsen, the senior copywriter at Sterling Cooper with a love for his liquor (Didn’t they all share this same affinity back then?) was played by Joel Murray. And yes, he is indeed the younger brother of veteran actor Bill Murray.

Joel Murray has had his own success as an actor, with roles in series like Dharma & Greg and Shameless.

Glen Bishop is Matthew Weiner’s Son

Glen Bishop from Mad Men

That creepy neighbor kid who was infatuated with Betty Draper was actually played by the son of Matthew Weiner, who created the series. The child did everything from watch Betty in the bathroom to go so far as to ask for a lock of her hair.

Throughout the series' run, Marten Weiner played the young boy who would visit the Draper household and try to spend time with Mrs. Draper any chance he could get, only to later turn his attention to her daughter Sally.

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Kiernan Shipka Never Watched The Show

Sally Draper sitting in a booth in Mad Men

Given that she was too young to watch, Kiernan Shipka, who played Sally, the eldest Draper child, never actually watched the show while she was on it. So she never saw her performance as the young and eventually teenage daughter of the distant and cold Don Draper.

Has she watched it today? Who knows. Now of age at 19 and starring in Netflix’s The Chilling Adventures of Sabrina, Shipka may have carved out some time to finally see her stellar work in the fantastic series.

Christina Hendricks Was Super Nervous About Playing Joan

If you look closely in her first scene of the series, you can see Christina Hendricks' hand shaking as she tries to light a (fake) cigarette. Her signature walk was also a by-product of the tight dresses she had to wear, forcing her to strut in such a way that became a defining part of her character.

As the office manager, Joan was always well put-together and confident.  Yet Hendricks was so nervous, and even mentioned that the old-fashioned lighters didn’t always work properly, adding to her anxiety.

Regardless of the nerves, they didn’t show unless you looked really closely, as Hendricks did an amazing job playing the flirtatious, strong, and independent character.

Ken Cosgrove Didn’t Know How to Smoke

Ken with a cigarette in his mouth in Mad Men

Despite actor Aaron Staton stating that he had smoked for a decade prior to getting the role of account executive Ken Cosgrove, everyone made fun of the way he smoked the fake cigarettes in the show, saying it looked as though he had never smoked before.

Because of the way he smoked at the beginning, which Weiner reportedly joked looked like a “d****ebag,” the character had to continue smoking in that same manner for the sake of consistency. Now you want to go back and watch it again, don’t you?

Roger Sterling Was Supposed to Die in Season 1

John Slattery as Roger Sterling in Mad Men

Roger Sterling had two heart attacks during the series, and his character was actually supposed to die in the first season. It makes sense since the series really centered around Don Draper and his rise to power in the advertising world. John Slattery, who played Sterling, also had another job, so it was unknown if he would be able to continue on the series.

We’re glad, however, that Sterling remained part of the firm, and a good friend and foil for Draper. Sterling Cooper and its later iterations would not have been the same without him.

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