The much-loved British actor first shot to stardom in 1988 when he played Bruce Willis’s adversary Hans Gruber in Die Hard, and he went on to gain a new generation of fans for his role as Professor Severus Snape in the Harry Potter films.
A family statement said: “The actor and director Alan Rickman has died from cancer at the age of 69. He was surrounded by family and friends.”
His death comes days after rock star David Bowie also died from cancer at the same age.
Fans expressed grief that the world has lost two significant artists in less than a week.
Thomson said that her tribute was “hard to write because I have just kissed him goodbye”.
In 2003’s Love Actually, they played married couple Harry and Karen.
“What I remember most in this moment of painful leave-taking is his humour, intelligence, wisdom, and kindness.
"His capacity to fell you with a look or lift you with a word,” she wrote.
“The intransigence which made him the great artist he was — his ineffable and cynical wit, the clarity with which he saw most things, including me, and the fact that he never spared me the view.
"I learned a lot from him.”
Thomson called Rickman “the ultimate ally” in life, politics, and art, saying she trusted him absolutely.
“He was, above all things, a rare and unique human being and we shall not see his like again,” she wrote.
Harry Potter author JK Rowling joined other stars paying tribute to Rickman on Twitter and passed condolences to his wife Rima, writing: “There are no words to express how shocked and devastated I am to hear of Alan Rickman’s death.
"He was a magnificent actor & a wonderful man.
“My thoughts are with Rima and the rest of Alan’s family. We have all lost a great talent.
"They have lost part of their hearts.”
Harry Potter cast members Daniel Radcliffe and Emma Watson also both remembered Rickman in touching tributes.
Radcliffe called him “undoubtedly one of the greatest actors I will ever work with”, while Watson said she felt lucky to have spent time with him.
“I’ll really miss our conversations. RIP Alan. We love you,” she wrote on Facebook.
He was a respected star of stage and screen, and worked behind and in front of the camera, with some of his work still to be released.
He has died just months ahead of a new film, Eye In The Sky, in which he stars alongside Helen Mirren and Aaron Paul, which is set to open in UK cinemas on April 8, according to IMDb.
The star had also completed another film set for release later this year called Alice Through The Looking Glass.
His career began on the stage after he graduated from prestigious drama school Rada, and he frequently returned to the theatre throughout his career.
Hailing from a working-class London family, he worked as a dresser before finding work with the Royal Shakespeare Company.
Rickman’s CV showcases a glittering career spanning almost four decades and featuring a list of hit films from Truly Madly Deeply to theatre credits including Private Lives and Antony And Cleopatra.
He may be best known to older fans as sadistic terrorist Gruber in Die Hard from 1988, or the villainous Sheriff of Nottingham in Robin Hood: Prince Of Thieves from 1991.
However, younger fans probably know him best for his turn as the morally ambiguous Snape in the hugely successful Harry Potter franchise.
Rickman, who was also a film-maker, said Rowling’s long-running Harry Potter series prevented him from returning to the director’s chair for almost two decades.
He directed and starred as French King Louis XIV alongside Kate Winslet in A Little Chaos, and on the red carpet at the Scottish premiere of the film last February, he said he had no idea Rowling’s saga would stretch to seven novels and eight films when he took the role of Snape in 2001.
A Little Chaos was the star’s second outing behind the camera, 18 years after he directed Emma Thompson in Scotland-based drama The Winter Guest.
Just last year he revealed he had married his high school sweetheart after 50 years together. Rickman had been in a relationship with Rima Horton since they met when he was 19 and she was 18.
The pair had been living together in London for 50 years, and Rickman revealed to German newspaper Bild last April that they recently tied the knot in secret.
Asked what the secret of his successful relationship was, though they were not married, he replied: “We are married, just recently. It was great because no one was there. After the wedding in New York, we walked across the Brooklyn Bridge and ate lunch.”
Rickman was also viewed by many as a movie heart-throb and, striking a blow for the more mature actor, he was ranked in seventh place in a sexiest actor list by Total Film magazine in 2013 at the age of 66, beating stars such as Brad Pitt and George Clooney.