Henry was born on 21st April 1842, in Great Ilford, the son of builder William Ashmole (1811-1879) and Charlotte Hunsdon (1814-1880). His paternal grandparents were Samuel Ashmole (1778-1818) and Sarah Darby. Henry had one brother William (Willie) Ashmole (1850-1924) an Auctioneer, Valuer and Estate Agent.
He married Sarah Ann Mackey (1846-1917) at St. John the Evangelist East Dulwich on 14th May 1868. The marriage sertificate records that he was a builder and bachelor aged 26. His bride was a 23-year-old spinster. Her father was George Mackey a wine merchant. They had three children; George William Ashmole 1869-1871; Sidney Ashmole 1870-1923 and Ernest Ashmole 1873-1916.
Henry died on 17th February 1879, aged 36, at Back Street, Ilford of pleurisy, which he had endured for six days. He was still a builder. His will dated 28th October 1874 was proved by his brother William Ashmole, Ilford Auctioneer & Surveyor on 5th March 1879. His effects were resworn in July 1880 at under £4,000.
His widow Sarah Ann Ashmole of Thorold Road, Ilford died on 20th February 1917. Administration of her will was granted on 17th March 1917 to Sidney Ashmole a cabinet maker. Her effects were valued at £218.75.
Henry had many paternal and maternal uncles and aunts and numerous cousins. His uncle, Henry Jubilee Ashmole (1813-1886), was landlord of the Angel Hotel, Ilford. His wife was Maria Oldaker. They and their 7 children are frequently mentioned in Henry's diary.
The diarist’s mother’s family, the Hunsdon’s, came from Little Ilford and farmed at the manor house. Henry’s nephew, the eminent classical scholar and Oxford Professor Bernard Ashmole (1894-1988), Keeper of Greek and Roman Antiquities at the British Museum, gives a brief account of the Ashmole family in his autobiography. One illustrious 17th century Royalist ancestor was Elias Ashmole (1617-1692). The flourishing Oxford Ashmolean Museum which Elias founded in 1683, has claim to be the first public museum in Europe.