He is known for his television roles as Cullen Bohannon in the AMC western drama series Hell on Wheels, as Jim Steele on the NBC series Conviction (2006), as the Marvel Comics superhero Black Bolt in the Marvel Cinematic Universe (MCU) media franchise (appearing in Inhumans and Doctor Strange in the Multiverse of Madness), and as Captain Christopher "Chris" Pike in the Star Trek television series Discovery, Short Treks (2019), and Strange New Worlds (2022–present).

In 2022, Mount portrayed Black Bolt in the Marvel Cinematic Universe (MCU) film Doctor Strange in the Multiverse of Madness, reprising his role from 2017's Inhumans.

[10] Mount is widely known for his role as Cullen Bohannon on AMC's hit series Hell on Wheels, which he also produced from 2014 to 2016.

[15] Mount is an adjunct assistant professor at Columbia University,[16] teaching audition technique for graduate actors.

[17] His non-fiction pieces have been published in the magazines Mosaic,[18] The Daily Beast[19] and Cowboys & Indians,[20][21] and in the Calgary Herald newspaper.