Production was moved from Ireland to England after writer, producer, and director Stanley Kubrick received word that his name was on an I.R.A. hit list for directing a movie featuring English soldiers in Ireland. Consequently, several scenes were dropped.
Stanley Kubrick used to play the soundtrack's classical music during takes to get the actors and actresses in a better mood. He was reportedly influenced by Sergio Leone's method in Once Upon a Time in the West (1968).
Many of the shots were composed and filmed in order to evoke certain eighteenth-century paintings, especially those by Thomas Gainsborough.
Contrary to legend, this movie did use artificial lighting in some scenes (for example, when Bryan (David Morley) learns he's getting a horse). However, it is true that no electronic lighting was used for the candle-lit scenes. A lens built by the Carl Zeiss Company for N.A.S.A., a 50mm Zeiss lens modified with the Kollmorgen adaptor used in still cameras, was used to shoot scenes lit only by candle. This lens had the largest aperture of any ever built for movie use (f/0.7).
Filming began on May 4, 1973 and ended on February 27, 1974 after 300 days, 9 months, or 42 weeks. The production suffered two major shutdowns, resulting in what was then considered a bloated $11 million budget. It was finally released on December 18, 1975.
Vivian Kubrick: The young girl sitting behind Lady Lyndon's left shoulder during the magic show is Stanley Kubrick's daughter.
Stanley Kubrick: [zoom] When the Grenadiers march in formation toward the Barryville citizens and fire their weapons into the air.
Stanley Kubrick: [faces] Captain Quin's (Leonard Rossiter's) face during his duel with Barry (Ryan O'Neal) when he goes to raise his pistol.