Trivia

Worked as a day-care teacher during college and, before moving to Hollywood, was a high school teacher.

Struggled with severe chronic depression in his early twenties after the death of his father.

Taught drama at his alma mater, John Burroughs High School in St. Louis, Missouri. One of his students was Ellie Kemper.

(Late March 2015) Completed a 30-day stint in rehab to treat his alcohol addiction. He previously admitted turning to alcohol to cope with his father's death in 1991, which made him also seek therapy.

Although his character Don Draper is famous for being a very heavy smoker, Hamm quit smoking when he was twenty-four and uses herbal cigarettes on ''Mad Men''.

Once worked as a set dresser for pornographic films.

Gave himself a career deadline, saying that he planned to move back home if his acting career did not gain momentum by the age of 30.

Very close friends with Paul Rudd.

Did not book a single acting job in the first three years of his career in Los Angeles.

His mother died when he was ten, and his father ten years later.

Was unable to find work in his mid twenties as most roles were for High school aged characters and he looked too old.

Role models are Jeff Bridges, Sam Elliott and Greg Kinnear.

Went to a prom with Sarah Clarke, who also later became a professional actress (24 (2001); the "Twilight" series).

Was represented by the famous William Morris Talent agency, but was dropped after failing to book a single part in three years.

Former partner of Jennifer Westfeldt, the actress and co-writer of Kissing Jessica Stein (2001). They were together from 1998-2015.

Attended Prince's very last concert, a 90-minute non-stop extravaganza at the Fox Theater in Atlanta, Georgia (April 2016).

Is a huge comedy fan and is known to frequently quote lines from ''Anchorman: The Legend of Ron Burgundy (2004)'' and comedy troupe ''The Kids in The Hall''.

Became a fan of cricket after being introduced by Daniel Radcliffe while making ''A Young Doctor's notebook''.

Starred in a video on the Shelter Me website to encourage dog adoption.

Became interested in acting in the first grade, when he was handpicked to play Winnie-the-Pooh. Received a scholarship to study acting at the University of Missouri.

Adopted his dog Cora, a mutt, from a shelter in 2003.

He is of German, English, and Irish ancestry.

Admitted that he resumed drinking in moderation after seeking alcohol treatment and abstaining from alcohol for 15 months. (2023)

Lives in ultra trendy Los Angeles neighborhood, Los Feliz. Giovanni Ribisi, Bo Barrett, Scarlett Johansson, Chris Pine, Brad Pitt, Mark Ruffalo, Kristen Stuart, Michael Cera, Hannah Telle and Robert Pattinson are among the other actors who also call Los Feliz home.

Is an avid St. Louis Cardinals baseball fan and narrated the 2011 Official World Series film.

Owns a home in the Upper West side of New York City.

Has two step-siblings.

Went to high school (John Burroughs High School in St. Louis) with Sarah Clarke.

Since September 2019, he has been the co-spokesperson and appeared in a series of commercials alongside Monty Geer for the Canadian food delivery app called SkipTheDishes.

Is a member of the Democratic party.

His break out roll as a actor was "We Were Soldiers".

Through Jon's paternal grandmother he can be traced back to Joseph Hall born c. 1794 in Woolley, near Wakefield, West Yorkshire, UK.