Parker was the first known African American student at Mount Holyoke. The Seminary did not know she was a woman of color until she arrived. Parker was remembered by her classmates as a quiet, modest student, noted especially for her musical ability and tenacity of her beliefs. A talented pianist, a classmate reportedly wrote, “In all these years I have never heard ‘Home Sweet Home’ played with such beauty and pathos as Hortense played it.” Parker graduated from Mount Holyoke as valedictorian of her class.
Shortly after graduation, she taught in schools in Indiana and New York and married O.M. Wood. In 1913 she married James Marcus Gilliam and moved to St. Louis, MO, where she continued to teach. Parker returned to the College in 1932, visiting several classmates and contributed to the centenary honor roll. She died in December 1938.