The Oscar winner, 33, portrays Harriet Mutesi, the mother of real-life chess prodigy Phiona Mutesi who despite their family's impoverished circumstances becomes a world champion, in the film, reported Contactmusic.
"There is an ease in the Ugandan demeanour that is very welcoming," she said.
"I love the melody of the accent, the food, the music and the people's inherent style. There was a familiarity with my home country, being right next door, but also complete surprise in what was so different. There is a resilience of spirit in Uganda.
The film is also her first onscreen role since her Oscar-winning performance in 2013's "12 Years a Slave". Over the past year, she has voiced characters in both "Star Wars: The Force Awakens" and "The Jungle Book" but she never actually appeared in either project.