Ian Slater was educated at Toowoomba State High School, Queensland. Before moving to Canada, Slater worked for the Australian Navy, then for the Department of External Affairs as a cipher clerk, then as a defence officer with the Australian Joint Intelligence Bureau. On his way to Canada he worked as a marine geology technician with the Institute of Oceanography in New Zealand, and later with the Institute of Oceanography at the University of British Columbia in Vancouver, Canada. He completed a BA, an MA and, in 1977, a PhD in political science from the University of British Columbia. He has taught in the humanities at various universities.
Slater's first publication was a short story, 'A Children's Tale', published in 1966 in the Australian anthology Under Twenty-Five. He began writing professionally in his early twenties. He wrote a biography of George Orwell, Orwell: The Road to Airstrip One (1985).