His parents, Philomena (née Norris) and naval officer Geoffrey Freeman, separated when he was a child.

[6] He began to move into more serious dramatic roles on television with his appearance as Lord Shaftesbury in the 2003 BBC historical drama Charles II: The Power and The Passion.

[8] In May 2009, he starred in Boy Meets Girl, a four-part drama that charts the progress of characters Veronica and Danny after an accident which causes them to swap bodies.

Freeman played lead character Bilbo Baggins in Peter Jackson's three-part The Hobbit film series.

[13] Freeman appeared in all three films of Simon Pegg and Edgar Wright's comedic Three Flavours Cornetto trilogy, commencing with a brief non-speaking role in Shaun of the Dead as Yvonne's boyfriend, Declan, followed by a brief cameo in Hot Fuzz as a police officer.

On 5 October 2013, he was presented with a fellowship bearing his name by the members of University College Dublin's Literary & Historical Society.

[19][20] Freeman also played Everett K. Ross,[21] a Central Intelligence Agency agent in Captain America: Civil War, which was released in May 2016.

[23][24] Later that year he appeared opposite Tamsin Greig in Labour of Love, a political comedy by James Graham, at the Noël Coward Theatre.

[25] Freeman portrayed fictional Labour MP David Lyons, whose modernising ideas pit him against the traditional left-wing constituency agent Jean Whittaker (Greig).

[25] In 2018, he reprised his role as Everett K. Ross in Black Panther, which was set around two weeks after the event in Captain America: Civil War, making it his second appearance in Marvel Cinematic Universe.

In June 2018, Freeman was part of To Provide All People, a BBC Wales drama celebrating 70 years of the National Health Service.

As a teenager, he supported the now-defunct political group Militant and volunteered with the Labour Party Young Socialists.