|Birth:||28 June 1854|
Spring Green, Sauk, Wisconsin, USA
|Death:||11 January 1964|
Sioux Falls, Minnehaha, South Dakota, USA
|Age:||109 years, 169 days|
Emma Maria Mercer (née Rutherford) (28 June 1854 - 11 January 1964) was an American centenarian. She may have been the world's second-oldest living person, behind Mary Kelly, when she died.
She was born as Emma Maria Rutherford in Spring Green, Sauk, Wisconsin to Andrew Stephenson and Sarah Ann (née Simons) Rutherford. She recalled with ease the first train to Lone Rock. As a young girl, she said farewell to soldiers leaving for the Civil War. In 1872, she attended the Ringling Brothers circus.
She married Samuel Mercer on 27 January 1872 in Arena, Iowa, Wisconsin. They first moved to Iowa and then to Green, Nodaway, Missouri, and finally settled in South Dakota in 1901. Samuel died in 1949. Mercer lived the remaining 15 years of her life in South Dakota, dying in Sioux Falls, South Dakota on 11 January 1964, aged 109 years, 169 days.