 Dickens joined the North-West Mounted Police as a Sub Inspector in Canada in 1874 shortly after the March West which brought the original police force of 300 members to the modern provinces of Saskatchewan and Alberta.He would remain in the force 12 years, serving at Fort Walsh, Fort Macleod and Fort Pitt, getting promoted to Inspector in 1880.During the North West Rebellion of 1885, Francis Dickens was in charge of the defence of Fort Pitt on the North Saskatchewan River.