Lagaan: Once Upon a Time in India, or simply Lagaan, (transl. Land Tax) is a 2001 Indian Hindi-language epic period sports drama written and directed by Ashutosh Gowariker. The film was produced by Aamir Khan, who stars alongside debutant Gracy Singh and British actors Rachel Shelley and Paul Blackthorne. Set in 1893, during the late Victorian period of British colonial rule in India, the film follows the inhabitants of a village in Central India, who, burdened by high taxes and several years of drought, are challenged by an arrogant British Indian Army officer to a game of cricket as a wager to avoid paying the taxes they owe. The villagers face the arduous task of learning a game that is alien to them and playing for a victory.

Produced on a budget of ₹25 crore (US$5.3 million), Lagaan was the most expensive Indian film at the time of its release. It faced multiple challenges during production: Khan was initially sceptical to star in a sports film, and later, prospective producers called for budget cuts and script modifications. Eventually, the film would become the maiden project of Aamir Khan Productions, and mark Khan's foray into film production. Gowariker was inspired by aspects of sports drama Naya Daur (1957) in developing the film. The language featured in the film was based on Awadhi, but was diluted with standard Hindi for modern audiences. Principal photography took place in villages near Bhuj. Nitin Chandrakant Desai served as art director, while Bhanu Athaiya was the costume designer. The original soundtrack was composed by A. R. Rahman, with lyrics written by Javed Akhtar.

Lagaan was theatrically released in India on 15 June 2001, clashing with Gadar: Ek Prem Katha. It received widespread critical acclaim for Gowariker's direction, Khan's performance, dialogues, soundtrack, and the film's anti-imperialist stance. With earnings of ₹65.97 crore (US$13.98 million) during its initial release, the film was the third highest-grossing Hindi film of 2001. Lagaan was screened at numerous international film festivals and garnered multiple accolades. It was the third, and as of 2025 the last, Indian film to be nominated for the Academy Award for Best Foreign Language Film after Mother India (1957) and Salaam Bombay! (1988). Lagaan became the most-awarded film at the 47th Filmfare Awards with eight wins, including Best Film, Best Director for Gowariker and Best Actor for Khan. At the 49th National Film Awards, the film won eight awards, including Best Popular Film.

The farmers of the village of Champaner, in the British Central India Agency, live under an oppressive and racist regime, paying land tax (lagaan) despite poverty and an irregular harvest caused by drought. Unable to bear the burden, they ask the king, Raja Puran Singh, for relief from lagaan. The king is watching a cricket match between British officers. When he meets the villagers later, the regiment's captain, Andrew Russell, proposes a cricket match against his team, allowing villagers exemption from lagaan for three years should they win; they would be liable for triple the usual tax should they lose. A young farmer named Bhuvan accepts Russell's wager, and the match is scheduled to take place after three months.

Preparations for the match start slowly, as Bhuvan fails to unite the village in believing they have a chance. The few players who have enlisted for his team, try unsuccessfully to learn the game. Russell's sister, Elizabeth, who is visiting from England and who empathises with the farmers, offers to coach Bhuvan's team. Bhuvan gets eleven players as needed to compete for the match, though one of them, Lakha, secretly schemes with Russell to play against his own team. Meanwhile, Russell is berated by senior officers for gambling with the regiment's treasury and is told that he will face punitive, disciplinary action should the British team lose the match. He tries unsuccessfully to stop Elizabeth coaching the rival team, but she continues as she is secretly infatuated with Bhuvan. Bhuvan himself is unaware, courting the village medic's daughter, Gauri.

The match is to be played over three days outside the cantonment grounds. On the first day, the British elect to bat (see: rules of cricket), and are aided by Lakha's sabotage and inexperience of the locals, in putting up a good score. That night, the farmers learn about Lakha's betrayal from Elizabeth. They attack him but Bhuvan stands in his defence. Lakha redeems himself the next day by playing exceptionally, triggering a British collapse that ends their innings at 322, still a formidable score. The locals' innings starts with promise, but they lose almost all their best batters early. Bhuvan steadies the innings on the third day. In the final over, he hits six runs off the last ball to win the match for his team. Coincidentally, dark clouds gather in the sky and it begins raining heavily, signalling an end to the drought. The locals celebrate wildly, and Elizabeth catches Bhuvan and Gauri embracing amidst the crowd.

Elizabeth bids goodbye to the villagers, who are grateful for her coaching. She resists telling Bhuvan about her feelings for him, choosing to return to England, where she lives out her life unmarried.

The narrator states that, following the defeat, Russell is relocated to Central Africa and the provincial regiment is disbanded; that Bhuvan married Gauri in a grand ceremony blessed by Raja Puran Singh himself; and although Champaner's triumph benefited the whole province, knowledge of the event has escaped historical record altogether.