In the 2008 docudramaThe Last Explorer, Diamond explored the story of his great-uncle George Elson, a Cree guide who helped to map Labrador as part of an ill-fated 1903 expedition with Leonidas Hubbard and Dillon Wallace, and a return voyage in 1905 with Hubbard's widow Mina Hubbard.
As of April 2011, Diamond is developing a project with Inuit filmmaker Zacharias Kunuk about the 18th conflict between Cree and Inuit, which lasted almost a century.
Reel Injun was inspired by Diamond's own experiences as a child in Waskaganish, where he and other Native children would play cowboys and Indians[disambiguation needed] after local screenings of Westerns in their remote community. Diamond remembers that although the children were in fact "Indians," they all wanted to be the cowboys. Afterwards, when he was old enough to move south to study, he would be questioned by non-Native people about whether his people lived in teepees and rode horses, causing Diamond to realize that their preconceptions about Native people were also derived from movies.