Brooks was born in the rural midwestern town of Sterling, Illinois and spent a large part of his life living there. He is an alumnus of Hamilton College, obtaining his B.A. in English Literature in 1966. He later obtained a J.D. from Washington and Lee University. He was a practicing attorney before becoming a full-time author, and now resides in Seattle, Washington with his wife, Judine.
Brooks had been a writer since high school, writing mainly in the genres of science fiction, western, fiction, and non-fiction. One day, in his early college life, he was given a copy of The Lord of the Rings by J.R.R. Tolkien, which inspired him to write in one genre. He then made his debut in 1977 with his first novel The Sword of Shannara. This novel became the first fantasy book ever to appear on the New York Times bestseller list, where it stayed for five months.