Welford was born on 9 September 1875 in Okolona, Mississippi as the daughter of Rev. Richard and Heddie Welford. She moved to the Gibson Country area with her family as an infant and remained there for her entire life.
Welford never married, but had a son, Leo Mathis (1899–1966). She worked as a homemaker. She was a member of Lane Chapel C.M.E. Church.
Welford died at Parkview Manor Health Care Center in Humboldt, Tennessee, on 14 November 1992, at the age of 117 years, 66 days. She was survived by four grandchildren, three great-grandchildren, 10 great-great-grandchildren, and two great-great-great-grandchildren.
Welford claimed birth in 1881 and a final age of 111, but research conducted by Jimmy Lindberg proves that she was six years older and the second-oldest person of all time upon her death. Her age was validated by LongeviQuest on 28 February 2024.
Welford became the oldest resident of the United States upon the 30 March 1988 death of Orpha Nusbaum. She would later break the longevity record for the country after surpassing the age of Augusta Holtz in late 1990. Her own record would be broken by Sarah Knauss in 1997.
Welford was the first validated American and second person globally to reach the ages of 116 and 117, after Frenchwoman Jeanne Calment. As of April 2024, she is the tenth-oldest person ever validated, remains the longevity recordholder of the states of Mississippi and Tennessee, and is the oldest African-American ever.
* Delphia S. Welford – Find A Grave
* “Delphia Welford” – The Jackson Sun, 17 November 1992