Galloway was born in Vancouver, and raised in Kamloops, British Columbia. He attended the University College of the Cariboo and the University of British Columbia. His debut novel, Finnie Walsh, was nominated for the Amazon.ca/Books in Canada First Novel Award. His second novel, Ascension, was nominated for the BC Book Prizes' Ethel Wilson Fiction Prize, and has been translated into numerous languages. His third novel, The Cellist of Sarajevo, was published in spring of 2008. It was heralded as "the work of an expert" by the Guardian, and has become an international bestseller with rights sold in 20 countries. Galloway has taught creative writing at the University of British Columbia and taught and mentored creative writing in The Writer's Studio, at the writing and publishing program at Simon Fraser University.