An Emmy Award-winner, Cox has also been nominated for Golden Globe, BAFTA and Screen Actors Guild Awards. In 2006, Empire readers voted him the recipient of the Empire Icon Award.
Cox was born in Dundee, the only son and youngest of five children. He is from a working class Roman Catholic family, of Irish and Scottish descent. His mother, Mary Ann Guillerline (née McCann), was a spinner who worked in the jute mills and suffered several nervous breakdowns during Cox's childhood. His father, Charles McArdle Campbell Cox, was a butcher and later a shopkeeper, and died when Cox was eight years old. Cox was brought up by his four elder sisters. He joined Dundee Repertory Theatre at the age of 14.
Cox was educated at St Mary's Forebank Primary School, followed by St Michael's Junior Secondary School (both in Dundee), which he left at the age of 15. After working at Dundee Repertory Theatre for a couple of years, he went to drama school from the age of 17 to 19, at the London Academy of Music and Dramatic Art.
Cox left the London Academy of Music and Dramatic Art in 1965 when he joined the Lyceum company in Edinburgh, followed in 1966 by two years with the Birmingham Rep, where his roles included the title role in Peer Gynt (1967) and Orlando in As You Like It, in which he made his London debut in June 1967 at the Vaudeville Theatre. He made his first television appearance in an episode of The Wednesday Play in 1965 and made one-off appearances in several other TV shows before taking a lead role in The Year of the Sex Olympics in 1968.
A recurring rumour that Cox made uncredited appearances as an extra in several episodes of The Prisoner was disproved by the actor in an interview with Bullz-Eye.com, where he confirmed, "I would’ve loved to have been in 'The Prisoner,' and I remember seeing it, and I watched it when it first came out. I’m old enough to have seen it and watched it and, yes, to have been an extra in it. But I never was." In 1978, he played King Henry II of England in the acclaimed BBC2 drama serial The Devil's Crown, following which he starred in many other television dramas. His first film appearance was as Leon Trotsky in Nicholas and Alexandra in 1971.
Cox is an accomplished Shakespearean actor, spending seasons with both the Royal Shakespeare Company and the National Theatre in the 1980s and 1990s. His work with the RSC included a critically acclaimed performance as the title character in Titus Andronicus, as well as playing Petruchio in The Taming of The Shrew. Cox said later that his performance in Titus Andronicus was "the greatest stage performance I've ever given." Later Cox portrayed Burgundy opposite Laurence Olivier in the title role of King Lear (1983). He went on to play King Lear at the National Theatre.
In 1986, during the production of Manhunter, while Cox was playing Hannibal Lecktor, Anthony Hopkins was playing King Lear on stage at the National Theatre. Five years later, during the production of The Silence of the Lambs in which Hopkins took over as the correctly named Lecter, Cox was playing King Lear at the National Theatre. At the time, the two actors shared the same agent.
In 1984, he played the Royal Ulster Constabulary officer Inspector Nelson in the Royal Court's production of Rat in the Skull. He was subsequently awarded that year's Laurence Olivier Award for 'Best Actor in a New Play'
In 1991, he played the role of Owen Benjamin, the closeted father of a gay man, in the BBC "Screen 2" production of David Leavitt's novel, The Lost Language of Cranes, which is set in the 1980s. In 1993 he appeared as British spymaster Major Hogan in two episodes of the British television series Sharpe. In the same year, he was seen in an episode of Inspector Morse ("Deadly Slumber"), where he portrayed Michael Steppings, a retired bookmaker whose daughter is in a permanent coma.
In 1994, he played the role of Colonel Grushko, 'a policeman who sees greed and rapacity in Russia's new mood', in Grushko, a British-made crime drama set in Russia.
His most famous appearances include Rob Roy, Braveheart (both in 1995), The Ring, X2, Troy and The Bourne Supremacy. He usually plays villains, such as William Stryker in X2, Agamemnon in Troy, Pariah Dark in the Danny Phantom television series episode Reign Storm, devious CIA official Ward Abbott in the first two Bourne films, and in Chain Reaction. In 2001, he received critical acclaim for his performance as a pedophile in Michael Cuesta's L.I.E.; he won a Satellite Award for Best Actor - Motion Picture Drama, and was nominated for an Independent Spirit Award for Best Lead Actor and an AFI Award for Featured Actor of the Year - Male.
He has played more sympathetic characters, such as Edward Norton's father in 25th Hour. Super Troopers saw him play a fatherly senior police officer.
He also played Rachel McAdams' father in Red Eye and appeared in the U.S. sitcom Frasier as the father of Daphne Moon (played by Jane Leeves). He was also the protagonist in the film The Escapist. Cox made a guest appearance in the 1997 Red Dwarf episode "Stoke Me a Clipper", as a medieval king in a virtual reality game. Cox was in L.I.E. (2001), in which he played a pedophile New Yorker. He won an Emmy Award and was nominated for a Golden Globe Award that year for his portrayal of Hermann Göring in Nuremberg, and also appeared as Jack Langrishe in the HBO series Deadwood.
In 2002, he appeared in Spike Jonze's Charlie Kaufman-scripted Adaptation as the real-life screenwriting teacher, Robert McKee, giving advice to Nicolas Cage in both his roles, as Charlie Kaufman and Charlie's fictional twin brother, Donald. In 2004, Cox played an alternate, villainous version of King Agamemnon in Troy. He appeared on a 2006 episode of the British motoring programme Top Gear (as a "Star in a Reasonably Priced Car"). Cox has also been involved in the video game industry. Among his most prominent roles were Killzone (2004), Killzone 2 (2009), and Killzone 3 (2011), in which he played the ruthless emperor Scolar Visari. Cox also was the voice of Lionel Starkweather, the main antagonist in the Sony PlayStation 2 game Manhunt (2003).
His radio work includes playing the title character in the BBC Radio 4 series McLevy (1999–present), based on the real life detective James McLevy. and his portrayal of the Dundonian comic character Bob Servant. Cox says he played Servant, the creation of Dundonian author Neil Forsyth, based on memories of his late brother Charlie. Cox narrated an abridged audiobook version of Sir Walter Scott's novel Ivanhoe, and an unabridged audio book of J.R.R. Tolkien's The Silmarillion. He has also collaborated with HarperCollins on an audiobook of Tolkien's epic poem The Legend of Sigurd and Gudrún.
In 2008, Cox starred in Red, based on Jack Ketchum's novel. The film was directed by Lucky McKee and Trygve Allister Diesen and also starred Tom Sizemore, Amanda Plummer, and Kim Dickens. Cox also played an institutionalized convict in Rupert Wyatt's film, The Escapist, appearing alongside Joseph Fiennes, Dominic Cooper and Damian Lewis.
In December 2009, Cox appeared in The Day of the Triffids, written by Patrick Harbinson, whose credits include ER and Law & Order. The drama is based on John Wyndham's best-selling post-apocalyptic novel, The Day of the Triffids. The same year, Cox provided the voice for the Ood Elder in part one of the Doctor Who Christmas Special, The End of Time. Cox starred in the Ridley Scott produced Tell-Tale, a film based on the short story "The Tell Tale Heart" by Edgar Allan Poe.
In February 2010, Cox was elected as Rector of the University of Dundee, polling almost two-thirds of the vote. Cox was set to portray Mr. Reisert in Scream 4, but it was later announced that he would not be joining the cast.
In February 2010, Cox played former House of Commons Speaker Michael Martin in the television film On Expenses. Cox played Laura Linney's father in the Showtime series The Big C. In July 2010, he joined the cast of the 2011 science-fiction film Rise of the Planet of the Apes.
In 2010, Cox appeared in another movie titled ″Red″, totally unrelated to the 2008 film cited above.
In 2011, Cox appeared on Broadway opposite Jason Patric, Chris Noth, Kiefer Sutherland and Jim Gaffigan in a revival of Jason Miller's That Championship Season, which opened in March. In January 2012, Cox appeared alongside Billy Connolly in BBC radio 4's Saturday Play — The Quest of Donal Q, specially written for the pair by David Ashton who also wrote the McLevy series. Cox appears in the Australian TV drama The Straits as the patriarch of the Montebello family crime syndicate, Harry Montebello. Shooting started on location at Cairns and the Torres Strait Islands in June 2011. The series premiered on Australian TV Channel ABC1 on 2 February 2012. His portrayal of Jack in The Weir at The Donmar Theatre in April 2013 is reprised at Wyndham's Theatre in January 2014.
In 2013, he appeared as Ivan Simanov in Red 2, duplicating the role from the 2010 original film. in November 2013, he starred in the BBC television docudrama, An Adventure in Space and Time, about the creation of the British science-fiction series Doctor Who. Cox portrayed Canadian television executive Sydney Newman, the driving force behind the creation of the iconic programme. In March 2015, he joined Emile Hirsch to the cast of The Autopsy of Jane Doe.
In the summer of 2016, Brian Cox directed the American premiere of Joshua Sobol's Sinners in Greensboro, VT and became co-artistic director of The Mirror Theater Ltd.
In June 2017 Cox starred in Churchill, playing the title role.
He is divorced from his first wife, Caroline Burt. The couple have two children, Margaret and Alan, who is also an actor, best known for his roles in Young Sherlock Holmes, and playing the young John Mortimer in the television film of his play A Voyage Round My Father (1982) opposite Laurence Olivier.
Cox wed his second wife, actress Nicole Ansari, in 2002. The couple have two boys and live in New York City.
In 2007, Cox campaigned for Labour in the run-up to that year's Scottish Parliamentary elections. Cox endorsed the Scottish National Party in the 2011 election, however, only because of their higher education policy. On 25 May 2012, Cox spoke in support of Scottish Independence at the Yes Scotland campaign. Although a Labour Party supporter and saying he believed in democratic socialism, he felt that Independence was the best way forward for Scotland.
On 29 January 2015, Cox announced he had quit the Labour Party as he believed it had failed to live up to its basic principles and instead joined the Scottish National Party as he felt it was taking forward values of social justice and representing Scotland's best interests.
Cox is a patron for Scottish Youth Theatre, Scotland's National Theatre "for and by" young people. Scottish Youth Theatre's building in Glasgow, The Old Sheriff Court, named their theatre the Brian Cox Studio Theatre in his honour. He is also a patron of "THE SPACE", a training facility for actors and dancers in his native Dundee, and an "ambassador" for the Screen Academy Scotland.
On 11 February 2010, Cox was elected as the 12th Rector of the University of Dundee by students of the institution. He was re-elected in January 2013. He holds an honorary doctorate from Napier University in Edinburgh, awarded in July 2008.
In April 2010, Cox, along with Ian McKellen and Eleanor Bron, appeared in a series of TV advertisements to support Age UK, the charity recently formed from the merger of Age Concern and Help the Aged. All three actors gave their time free of charge.
On 14 April 2012, Cox was the 10th Grand Marshal of the New York City Tartan Day Parade.
On 31 December 2002, Cox was appointed a Commander of the Order of the British Empire in the New Year Honours List.