Guiteau was born in Illinois, to Luther Wilson Guiteau and Jane Guiteau nee Howe. Guiteau's mother was noted for her longevity, living to be nearly 110 years old before her death in 1927. Guiteau and his family moved to Wisconsin when he was just nine years old. He lived there for most of his early life. In primary school, Guiteau had numerous difficulties and nearly failed out, but the loving encouragement of his father and mother allowed him to graduate at the top of his high school class. Guiteau later attended Harvard University, graduating magna cum laude with a major in law.