William Harrison Ainsworth (February 4, 1805 - January 3, 1882) was an English historical novelist. He was born in Manchester, England, the son of a solicitor. He was himself trained in the law, but the legal profession had no attraction for him, and going to London to complete his studies he made the acquaintance of John Ebers, publisher, and at that time manager of the Opera House, by whom he was introduced to literary and dramatic circles, and whose daughter he afterwards married. For a short time he tried the publishing business, but soon gave it up and devoted himself to journalism and literature his first success as a writer of romance being scored with Rookwood in 1834, of which Dick Turpin is the leading character; and thenceforward he continued to pour forth till 1881 a stream of novels, to the number of 39. Tower of London was his fourth work, and, according to Ainsworth himself, it was written chiefly with the aim of interesting his fellow-countrymen in the historical associations of the Tower. Ainsworth died in Reigate on January 3, 1882.
Ainsworth depends for his effects on striking situations and powerful descriptions: he has little humour or power of delineating character.