William Timothy O'Brien was born in Minnesota in 1946. He attended Macalester College in St. Paul and earned a bachelor's degree in 1968. Soon after he graduated, he was drafted into the U.S. Army, where he served in combat in Vietnam for two years. He was awarded the Purple Heart after being wounded by flying shrapnel. After leaving the military, O'Brien attended Harvard and worked briefly for The Washington Post. In 1973, he published his first novel, If I Die in a Combat Zone, Box Me Up and Ship Me Home, obviously a war novel. Other novels O'Brien published include Northern Lights (1975) and The Things They Carried (1990).

Much of O'Brien's fiction is based on his war experiences. He uses his knowledge of combat to explore themes related to violence, courage, imagination, and reality. In spite of his own experiences, though, O'Brien's stories are more than just memoirs. If fact, he often blends fact and fiction to create gripping emotional stories and strong characters that focus on the horrors of war in the late 20th century, as well as timeless issues that affect everyone.