Hooper was the first child of five, born in Boston, Massachusetts, on June 28, 1742. His father, William Hooper, was a Scottish minister who studied at the University of Edinburgh prior to immigrating to Boston, and his mother, Mary Dennie, was the daughter of John Dennie, a well-respected merchant from Massachusetts. Hooper’s father had hoped that Hooper would follow in his footsteps as an Episcopal minister, and at the age of seven placed Hooper in Boston Latin School headed by Mr. John Lovell, a highly distinguished educator in Massachusetts. In 1757, at the age of sixteen, Hooper entered Harvard University where he was considered an industrious student and was highly regarded. In 1760 Hooper graduated from Harvard with honors, obtaining a Bachelor of Arts. However, after graduating, Hooper did not wish to pursue a career in the clergy as his father had hoped. Instead, Hooper decided on a career in law, studying under James Otis, a popular attorney in Boston who was regarded as a radical. Hooper studied under Otis until 1764, and once completing his bar exam decided to leave Massachusetts in part due to the abundance of lawyers in Boston.