Turnbull was born on August 12, 1987 in Maryland, but moved with his parents when he was a month old[3] and was raised in St. Thomas, U.S. Virgin Islands.

He moved to Pittsburgh to attend La Roche University,[3][4] where he received a BA in Professional Writing.

[5] He attended North Carolina State University for graduate school,[6] where he studied under John Kessel and Wilton Barnhardt.

His writing often addresses sociopolitical topics like colonialism and post-colonialism,[24][25] marginalized communities,[26][27] climate change,[28][29] police violence,[30][31] and collective ownership.

[29] He credits Ursula Le Guin as influential to his writing[32] along with Octavia Butler, Ted Chiang, N. K. Jemisin, Alice Munro, and George Orwell.