Alejandro Gonzalez Inarritu ("Babel") is directing the film, a gritty tale of survival and retribution set against the backdrop of the American frontier.
Based on the novel by Michael Punke, "The Revenant" tells the story of Hugh Glass (DiCaprio), a fur trapper who is robbed and left for dead by his cohorts after being mauled by a grizzly bear. After somehow living through the ordeal, Glass sets out to exact revenge against those who betrayed him.
No details were provided about Hardy's character.
"The Revenant" has also enlisted cinematographer Emmanuel Lubezki, fresh off an Oscar win for "Gravity." The film is set to begin production in September, with a fall 2015 release planned.
Hardy, who recently earned fine notices for his one-man movie "Locke," has had a packed schedule of late. His upcoming projects include the post-apocalyptic reboot "Mad Max: Fury Road," the period gangster film "Legend" and the 9/11 drama "The True American."
DiCaprio most recently starred as the shady stockbroker Jordan Belfort in "The Wolf of Wall Street." Inarritu's next movie, "Birdman," was also shot by Lubezki and opens in October.
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