Edward was the son of Edward Hannes of Devizes, Wiltshire. Peter Le Neve, who questioned Hannes' right to bear arms, states that his father "kept an herb shop in bloomsbury mercate". In 1678, he was admitted on the foundation at Westminster School, whence he was elected a student of Christ Church, Oxford, in 1682. He graduated BA in 1686 and MA in 1689. He contributed to the collections of Oxford poems on the death of Charles II, in 1685, and on William III's return from Ireland in 1690 (reprinted in 'Musarum Anglicanarum Analecta'). In 1688, he assisted William King (1663-1712) in writing 'Reflections on Mr. Varillas his history of Heresy, Book 1, Tome 1, as far as relates to English Matters, more especially those of Wicliff,' printed probably at Amsterdam (1688). Addison addressed a Latin poem to him. Hannes succeeded Robert Plot as reader in chemistry at Oxford in 1690. At the entertainment given to Ashmole by the vice-chancellor and heads of houses, in the Museum at Oxford on 17th July 1690, Hannes addressed Ashmole in an eloquent speech. He proceeded MB in 1691 and MD in 1695; attended William, Duke of Gloucester, at his death on 30th July 1700, and published an account of the dissection of the body. For this account, he was ridiculed in a satirical poem entitled 'Doctor Hannes dissected in a familiar epistle by way of Nosce Teipsum' (1700). He became physician to Queen Anne in June 1702, and was knighted at Windsor Castle on 29th July 1705. He died on 22nd July 1710 in the parish of St. Anne, Westminster and was buried beside his wife at Shillingford in Berkshire, where there is a monument to his memory. He married (articles dated 30th September 1698) Anne, daughter of Temperance Packer, widow, of Donnington Castle House, Berkshire, by whom he had an only child, Temperance. By his will, he gave £1,000 towards finishing Peckwater quadrangle at Christ Church and £1,000 towards the erection of a new dormitory at Westminster School. He had previously presented, to the school, a handsome drinking goblet ('poculum') for the use of the queen's scholars there.

Edited from Leslie Stephen & Sidney Lee's 'Dictionary of National Biography' (1890).