Rickman's family said Thursday that the actor had died after a battle with cancer.
Born to a working-class London family in 1946 and trained at the prestigious Royal Academy of Dramatic Art, Rickman was often cast as the bad guy; with his rich, languid voice he could invest evil with wicked, irresistible relish.
His breakout role was as scheming French aristocrat the Vicomte de Valmont in an acclaimed 1985 Royal Shakespeare Company production of Christopher Hampton's "Les Liaisons Dangereuses."
Film roles included the psychopathic villain Hans Gruber who tormented Bruce Willis in "Die Hard" in 1988; a deceased lover who consoles his bereaved partner in 1990's "Truly Madly Deeply"; the wicked Sheriff of Nottingham in "Robin Hood: Prince of Thieves" in 1991; and a wayward husband in 2003 romantic comedy "Love Actually."
Millions know him from the Potter films, in which he played the potions and defense against the dark arts teacher Severus Snape, who was either a nemesis or an ally — possibly both — to the titular teenage wizard.
His villains were memorable, and included an Emmy-winning turn as "mad monk" Rasputin in a 1996 TV biopic.
But Rickman's screen roles were remarkably varied, and included the upright Col. Brandon in Ang Lee's 1995 film version of "Sense and Sensibility" and Irish politician Eamon de Valera in 1996 historical drama "Michael Collins."
He had a sideline in comic sci-fi, bringing knowingness and fun to the spoof "Galaxy Quest" in 1999 and delivering existential ennui as the voice of Marvin the Paranoid Android in "The Hitchhiker's Guide to the Galaxy" in 2005.
He appeared frequently onstage, earning Tony Award nominations for "Les Liaisons Dangereuses" in 1987 and Noel Coward's "Private Lives" in 2002.
Rickman was also a filmmaker, directing and co-starring opposite Kate Winslet in 2014 costume drama "A Little Chaos." Seventeen years earlier, he'd directed Emma Thompson and her mother Phyllida Law in "The Winter Guest."
Frequently charming in person, Rickman was, by his own account, uncompromising as an actor. During the filming of "Harry Potter," he maintained Snape's air of haughty disdain even off-camera.
"The animal in me takes over," Rickman told The Associated Press in 2011 when he appeared on Broadway in Theresa Rebeck's play "Seminar."
"You're as polite as possible, but it's not always possible."
Rickman is survived by his partner of 50 years, Rima Horton, whom he married in 2012. Funeral details were not immediately available.
— JILL LAWLESS, Associated Press