Blackman was born in Chattanooga, Hamilton County, Tennessee, USA, on 24 October 1905. Her parents were Ambrose Walter Phelps (1863–1935) and Agnes Keebler (1866–1960).
In 1927, she married Ralph Prudon Blackman (1903–1981). Following the marriage, the couple moved to Portsmouth when her husband got a job at the Navy shipyard in Norfolk. The couple had two daughters: Barbara Ann Wynne and Elizabeth Johnson. In the late 1940s, she began volunteering with the Girl Scouts while seeking to participate in her daughters’ activities. Being a skilled seamstress, she assisted the girls in her troop in achieving their sewing badges. Even after her daughters finished with Girl Scouts, she remained dedicated to supporting the organization for as long as possible. She spent many years training troop leaders entering the organization.
Blackman passed away in Portsmouth, Virginia, USA, on 15 June 2017, at the age of 111 years, 234 days. She was survived by two daughters, four grandchildren, six great-grandchildren, and two great-great-grandchildren.
On 3 June 2017, following the death of 112-year-old Lizzie Wood, she became the oldest (known) living person in the U.S. state of Virginia. She held the title for 12 days. Following her passing, she was succeeded by 111-year-old Lillian Stubbs.
Her age was validated by LongeviQuest on 2 November 2023.
* “Ruth Eleanor Blackman” – Find A Grave
* “Finally a Girl Scout — at 106 years old” – Suffolk News-Herald, 17 December 2011
* “Ruth Phelps Blackman” – Sturtevant Funeral Home