She was born in Fort Jessup, Sabine Parish, Louisiana, to Albert Gallatin Blanchard, a military officer, and Susan Thompson.

[1][2] Elder was born on April 19, 1835, in Fort Jessup, Sabine Parish, Louisiana, to Albert Gallatin Blanchard, a military officer in both the U.S. and Confederate armies, and Susan Thompson.

She later returned to Louisiana as a teenager and received education at the Girls' High School of New Orleans and St. Michael's Convent of the Sacred Heart in St. James Parish.

After the war, they returned to New Orleans, where Elder pursued a career in education, teaching math and natural science at various institutions.

[1][2] Susan Blanchard Elder's notable literary contributions include The Life of Abbé Adrien Rouquette (1913), a biographical study of the poet-priest and missionary to the Louisiana Choctaw Native Americans.