Emily Underdown was born on 28 July 1863 at Higher Broughton, Lancashire, England. Her parents were Lieutenant-Colonel Robert George Underdown and Lydia Underdown (née Dacombe). She was the second of four children. Not much is known about her early life other than her graduation from University College London in 1898 (UCL Record Office).
She lived in Lancashire and Yorkshire during her early life, moving to London at some point after 1901. She did not marry. She died in London on 5 September 1947. Her brother, Herbert William Underdown was a solicitor and a well-known art collector and antiquarian scholar. In 1949, her Dante collection was bequeated to the London Library.
