Director John Crowley divided this movie into three different visual movements. The first movement is before Eilis Lacey leaves post-war Ireland and is with tight frames and filled with green tones. The color scheme was created by photographic reference of the time. The second movement begins when Eilis leaves for Brooklyn, and the first proper wide shot is featured, while the colors become more playful as a nod to how America in 1952 was on the cusp of pop culture kicking off. The third movement is back in Ireland, brighter, more glamorous, and "subtly more colorful" than the first movement. Crowley wanted to showcase how Eilis has changed and looks very different: "There is a slightly dreamy quality to that last third," he said.
The city of Brooklyn, New York, in this movie, was shot in Montreal, Québec, for budgeting reasons, as the production could not turn 2015 Brooklyn back into 1950s Brooklyn. Only two days of production were spent in Brooklyn, one to create the brownstone exterior shots and a second to film at Coney Island.
Irish author Colm Tóibín's idea for the novel came from a childhood memory in which he overheard a woman talk about her young daughter's move from Enniscorthy to Brooklyn. In 2000, he wrote a short story about this memory. Still, he expanded it to a novel years later, after living in the United States, as well as teaching literary courses, where he said he was inspired by Jane Austen's "method of examining a single psychology, using an introspective, sensitive heroine, some comic characters and some romance."
Rooney Mara was originally cast in the lead role. However, her eventual replacement, Saoirse Ronan, was a frontrunner for the part since this movie began development, but she was too young to portray Eilis. The production was stalled for years, Mara backed out, and when the project was ready to resume, Ronan had appropriately aged to fit the character and won the part.
Saoirse Ronan was born in The Bronx, New York, but raised in Ireland by Irish parents. She considers this movie one of her most personal movies, marking the first time she played an Irish character in a film. (In The Grand Budapest Hotel (2014), she spoke with an Irish accent but played a citizen of a generic fictitious European country.) In an interview with David Poland, she expressed concern about taking the role: "I felt like I can't mess this up because all of Ireland will be watching. I felt a huge responsibility to the country to capture the story." However, she said the warm reception at the Sundance Film Festival made her realize the universal essence of this movie.
Colm Tóibín: The book's author as a passenger in front of Eilis when she goes through Customs after arriving in New York.