- Father: James Blackwood
- Marriage: William Blackwood married Anna Eliza Blake, daughter of William Jex Jex Blake and Maria Lubbock, on Tuesday, 9 May 1843 in St Andrew's Church, Lammas with Little Hautbois, Norfolk, England. By Licence.
- Occupation: William was a Barrister at law.
- Residence: In 1843 William lived in Saintfield, Co Down, Ireland.