Trivia

Michael Collins adopted guerrilla tactics used by the Boers during the Second Boer War (1899-1902).

Despite containing several brutal scenes of violence, the film was given a very lenient 'PG' rating in Ireland mainly because of its historical context. Sheamus Smith issued a press statement defending his decision, claiming the film was a landmark in Irish cinema and that he believed "because of the subject matter, parents should have the option of making their own decision as to whether their children should see the film or not." The quad poster used to advertise the film in Ireland carried a message that read, "WARNING TO PARENTS AND GUARDIANS: This film includes scenes depicting explicit cruelty and violence along with crude language. It is advised that children under 12 years be accompanied by a parent or adult guardian." It became the second most successful movie ever released in Ireland.

The Treaty ports were returned to Ireland in 1938, ensuring the country could remain neutral throughout World War II.

Liam Neeson was 43 when this movie was made. The real-life Michael Collins was 31 when he died. Collins was only 5'10". whereas Neeson is 6'3".

Brendan Gleeson played Collins in The Treaty (1991). Liam Neeson consulted with Gleeson during pre-production and on-set on portraying the character.