Gambon married mathematician Anne Miller in 1962 when he was just 22 years old, but has always been secretive about his personal life, responding to one interviewer’s question about her: “What wife?”. The couple lived near Gravesend, Kent. They have one son, Fergus, a ceramics expert on the BBC’s Antiques Roadshow.

He made his film debut in the Laurence Olivier’s Othello alongside Maggie Smith in 1965. After his film debut in Olivier’s Othello, he subsequently played romantic leads, notably in the BBC television series The Borderers (1968–70), in which he was swashbuckling Gavin Ker. As a result, Gambon was asked by James Bond producer Cubby Broccoli to audition for the role in 1970, to replace George Lazenby.

After three years at the Old Vic, Olivier advised Gambon to gain experience in provincial rep. In 1967, he left the National Theatre for the Birmingham Repertory Company, which was to give him his first crack at the title roles in Othello (his favourite), Macbeth and Coriolanus.

His rise to fame began in 1974 when Eric Thompson cast him as the melancholy vet in Alan Ayckbourn’s The Norman Conquests at Greenwich. A speedy transfer to the West End established him as a comic actor, squatting at a crowded dining table on a tiny chair and agonising over a choice between black or white coffee.

This was to serve him in good stead in John Dexter’s masterly staging of The Life of Galileo in 1980, the first Brecht to become a popular success. Hall called him “unsentimental, dangerous and immensely powerful,” and The Sunday Times called his performance “a decisive step in the direction of great tragedy… great acting,” while fellow actors paid him the rare compliment of applauding him in the dressing room on the first night.

His craggy looks soon made him into a character actor, although he won critical acclaim as Galileo in John Dexter’s production of The Life of Galileo by Brecht at the National Theatre in 1980. But it was not until Dennis Potter’s The Singing Detective (1986) that he became a household name. After this success, for which he won a BAFTA, he famously starred as Georges Simenon’s detective Inspector Jules Maigret in an ITV adaptation of Simenon’s series of books. In 1989, Gambon starred in the acclaimed and controversial Peter Greenaway film The Cook, the Thief, His Wife & Her Lover, which also starred Helen Mirren.

In 1990 he played Jerry in Harold Pinter’s Betrayal for BBC Radio 3. He also made television appearances in series such as Wives and Daughters (1999) (for which he won another BAFTA). He later starred as Fyodor Dostoyevsky in the Hungarian director Károly Makk’s film The Gambler (1997) about the writing of Dostoyevsky’s novella The Gambler. In the 1990s he appeared in films such as, Toys (1992), Dancing at Lughnasa (1998), Plunkett & Macleane (1998), and Sleepy Hollow (1999).

There were also appearances in Harold Pinter’s Old Times at the Haymarket Theatre and Ben Jonson’s Volpone and the brutal sergeant in Pinter’s Mountain Language. David Hare’s Skylight, with Lia Williams, which opened to rave reviews at the National in 1995, transferred first to Wyndham’s Theatre and then on to Broadway for a four-month run which left him in a state of advanced exhaustion. “Skylight was ten times as hard to play as anything I’ve ever done” he told Michael Owen in the Evening Standard. “I had a great time in New York, but wanted to return.”

In the New Year Honours 1998, Gambon was appointed a Knight Bachelor for services to drama, and, on 17 July 1998, was invested by Prince Charles at Buckingham Palace.

Ralph Richardson dubbed him The Great Gambon, an accolade which stuck, although Gambon dismisses it as a circus slogan. But as Sheridan Morley perceptively remarked in 2000, when reviewing Nicholas Wright’s Cressida: “Gambon’s eccentricity on stage now begins to rival that of his great mentor Richardson”. Also like Richardson, interviews are rarely given and raise more questions than they answer. Gambon is a very private person, a “non-starry star” as Ayckbourn has called him. Off-stage he prefers to stay out of the limelight. While he has won screen acclaim, his ravaged King Lear at Stratford, while he was still in his early forties, formed a double act with a red-nosed Antony Sher as the Fool sitting on his master’s knee like a ventriloquist’s doll.

In 2001, he played what he described as “‘a physically repulsive” Davies in Patrick Marber’s revival of Pinter’s The Caretaker, but he found the rehearsal period an unhappy experience, and felt that he had let down the author. A year later, playing opposite Daniel Craig, he portrayed the father of a series of cloned sons in Caryl Churchill’s A Number at the Royal Court, notable for a recumbent moment when he smoked a cigarette, the brightly lit spiral of smoke rising against a black backdrop, an effect which he dreamed up during rehearsals.

While filming Gosford Park, Gambon brought Philippa Hart on to the set and introduced her to co-stars as his girlfriend. When the affair was revealed in 2002, he moved out of the marital home and bought a bachelor pad. The couple have been together since 2000, when they worked together on Channel 4 series Longitude. In February 2007, it was revealed that Hart was pregnant with Gambon’s child, and gave birth to son, Thomas, in May 2007. On 22 June 2009, she gave birth to her second child, a boy named William, who is Gambon’s third child.

Gambon is a qualified private pilot and his love of cars led to his appearance on the BBC’s Top Gear programme in December 2002. Gambon raced the Suzuki Liana and was driving so aggressively that it went round the last corner of his timed lap on two wheels. The final corner of the Top Gear test track has been named “Gambon” in his honour.

In 2003, he appeared with Robert Duvall and Kevin Costner, playing the principal villain in the Western film Open Range. In 2004, he appeared in five films, including Wes Anderson’s cult comedy The Life Aquatic with Steve Zissou; the British gangster film Layer Cake; theatrical drama Being Julia.

In 2004, Gambon played the lead role (Hamm) in Samuel Beckett’s post-apocalyptic play Endgame at the Albery Theatre, London. In 2005 he finally achieved a lifelong ambition to play Falstaff, in Nicholas Hytner’s National production of Henry IV, Parts 1 and 2, co-starring with Matthew Macfadyen as Prince Hal.

His best-known role is perhaps that of Albus Dumbledore, Hogwarts’ headmaster in the third instalment of J. K. Rowling’s franchise, Harry Potter and the Prisoner of Azkaban, taking over the role after the death of Richard Harris. (Harris had also played Maigret on television four years before Gambon took that role.) Gambon reprised the role of Dumbledore in Harry Potter and the Goblet of Fire, which was released in November 2005 in the United Kingdom and the United States. He returned to the role again in the fifth film, 2007’s Harry Potter and the Order of the Phoenix, and the sixth film, Harry Potter and the Half-Blood Prince. He appeared in the seventh film; Harry Potter and the Deathly Hallows Parts I and II, released in two parts in 2010 and 2011. Gambon told an interviewer that, when playing Dumbledore, he does not “have to play anyone really. I just stick on a beard and play me, so it’s no great feat. I never ease into a role—every part I play is just a variant of my own personality. I’m not really a character actor at all…'”

In 2006, He performed as Joe in Beckett’s Eh Joe, giving two performances a night at the Duke of York’s Theatre in London. That same year he played Henry in Stephen Rea’s play about Samuel Beckett’s Embers for Radio 3. In 2007 he was Sam in Harold Pinter’s The Homecoming for Radio 3. After Pinter’s death on 24 December 2008, Gambon read Hirst’s monologue selected by the playwright for Gambon to read at his funeral, held on 31 December 2008, during the cast’s memorial remarks from the stage as well as at the funeral and also in Words and Music, transmitted on the BBC Radio 3 on 22 February 2009.

He appeared on the programme again on 4 June 2006 and set a time in the Chevrolet Lacetti of 1:50.3, a significant improvement on his previous time of 1:55. He clipped his namesake corner the second time, and when asked why by Jeremy Clarkson, replied, “I dunno, I just don’t like it.”

In 2007, Gambon appeared in Michael Apted’s historical drama Amazing Grace alongside Ioan Gruffudd, Romola Garai, Benedict Cumberbatch, Albert Finney, Rufus Sewell. The film focuses on William Wilberforce who led the campaign against the slave trade in the British Empire. The film is Certified Fresh according to Rotten Tomatoes with critics consensus describing the film as “your quintessential historical biopic: stately, noble, and with plenty of electrifying performances.” That same year he played major roles the acclaimed BBC five-part adaptation of Mrs Gaskell’s Cranford novels alongside Judi Dench, and Imelda Staunton and in Stephen Poliakoff’s Joe’s Palace.

In 2008, Gambon appeared in the role of Hirst in No Man’s Land by Harold Pinter in the Gate Theatre, Dublin, opposite David Bradley as Spooner, in a production directed by Rupert Goold, which transferred to the London West End’s Duke of York’s Theatre, for which roles each received nominations for the 2009 Laurence Olivier Award for Best Actor.

In 2009, he appeared in a television adaptation of Jane Austen’s famously irrepressible Emma, a four-hour miniseries that premiered on BBC One in October 2009, co-starring Romola Garai. He played Mr. Woodhouse for which he received a 2010 Primetime Emmy Award for Outstanding Supporting Actor in a Miniseries or a Movie nomination for his performance.

In late 2009, Gambon had to withdraw from his role of W. H. Auden in The Habit of Art (being replaced by Richard Griffiths) because of ill health. In April 2010, Gambon returned once again to the Gate Theatre Dublin to appear in Samuel Beckett’s Krapp’s Last Tape, which transferred to London’s Duchess Theatre in October 2010.

In 2010 Gambon also appeared in Tom Hooper’s acclaimed historical drama The King’s Speech as King George V, alongside Colin Firth, Geoffrey Rush, Helena Bonham Carter, and Guy Pearce. The film received widespread critical acclaim, the review aggregator Rotten Tomatoes reporting the film with a score of 95% Certified Fresh with the website’s critical consensus reading: “Colin Firth gives a masterful performance in The King’s Speech, a predictable but stylishly produced and rousing period drama. In 2011, the film received 12 Academy Awards nominations, more than any other film in that year. The film won four Oscars including Best Picture, Director, Actor, and Adapted Screenplay.

That same year, Gambon appeared in the 2010 Christmas Special of Doctor Who, “A Christmas Carol”. During the 2010s he has also known for his voice work. He appeared as the Narrator in the British version of Kröd Mändoon and the Flaming Sword of Fire. In 2013, Gambon provided the voice for The Prophet, a character in the MMORPG video game The Elder Scrolls Online. Gambon has performed voiceover for the Guinness ads with the penguins.

In 2012 he played a role in Dustin Hoffman’s directorial debut with Quartet, based on the same-titled play by Ronald Harwood and starring Maggie Smith, Tom Courtney, Billy Connolly and Pauline Collins. The film premiered at the 2012 Toronto International Film Festival to favourable reviews. The review aggregator website Rotten Tomatoes reported an 80% approval rating with the consensus reading, “It’s sweet, gentle, and predictable to a fault, but Dustin Hoffman’s affectionate direction and the talented cast’s amiable charm make Quartet too difficult to resist.” Also in 2012, he starred with Eileen Atkins in an adaptation of Beckett’s radio play, All That Fall. Its premiere was at the Jermyn Street Theatre and it later transferred to the Arts Theatre. All That Fall had such good reviews in London that they took it to New York. In New York, they recast the role of Jerry and Liam Thrift got the part. They were a huge hit in New York, in 2013, and sold out the whole run after 4 days. In 2012, Gambon reunited with Dustin Hoffman in the HBO horse-racing drama Luck, which was canceled in March 2012 after three horses died on set.

In 2014, he was cast in the role of Howard Mollison on the upcoming adaptation of the best-selling book The Casual Vacancy by author J. K. Rowling, who is also the author of the Harry Potter books. The BBC One miniseries, being produced in association with HBO, will comprise three one-hour parts. Production begun 7 July 2014 in South West England.

In early 2015, Gambon announced that due to the increasing length of time it was taking him to memorise his lines, he was giving up stage work. He stated that “It’s a horrible thing to admit”. He had previously tried using an earpiece and being given prompts by theatre staff, but found this unsatisfactory, saying that “after about an hour I thought, ‘This can’t work. You can’t be in theatre, free on stage shouting and screaming and running around, with someone reading you your lines.'”

In 2015 and 2018, Gambon starred as Henry Tyson in the first and third series of Sky Atlantic’s Fortitude.

In 2016, Gambon was the narrator for the Coen Brothers’ Hollywood comedy Hail, Caesar! satirizing the 1950s Hollywood film industry. The ensemble also features Josh Brolin, George Clooney, Ralph Fiennes, Channing Tatum, Scarlett Johansson, Alden Ehrenreich, Tilda Swinton, Jonah Hill, Frances McDormand, Alison Pill and Clancy Brown. The film was well received by critics earning an approval rating of 86% on Rotten Tomatoes with the consensus being, “Packed with period detail and perfectly cast, Hail, Caesar! finds the Coen brothers delivering an agreeably lightweight love letter to post-war Hollywood.” The film also received an Academy Award nomination for its Production Design. He found the role opposite Bill Nighy, Toby Jones and Catherine Zeta-Jones in the war comedy film Dad’s Army (2016), based on the television sitcom of the same name.

In 2019, he appeared in the biographical film Judy, about Judy Garland starring Renée Zellweger, Rufus Sewell, Finn Wittrock and Jessie Buckley.