Her mother also soon died,[2] as did her stepmother,[4] and it was left to her maternal grandmother, S. Myra Cox Smith, to restore the family fortune during Reconstruction.

[3] In 1922[6] Somerville ran for the Mississippi House of Representatives, winning one of the seats in the at-large district in the Democratic Party primary.

During her term of office, she championed progressive causes and held the governor, Henry L. Whitfield, to his campaign pledge of appointing women to state boards.

Furthermore, during the Great Mississippi Flood of 1927, she refused, as a state representative, to evacuate her property, leading to an angry response from officials of the American Red Cross.

[3] A product of her time and place, she became increasingly more conservative as she grew older; she opposed the New Deal, was against pacifism, supported the poll tax, and rejected federal child labor laws, and by 1948 was an active States' Rights Democrat.

She was known as a shrewd businesswoman, who began investing in real estate after her husband's death; over the rest of her life she took what had been a small inheritance and grew it substantially, to the point that her banker considered her the most gifted investor he had ever known.

"[6] She self-identified as a Southerner for much of her life, once claiming that she had not felt like an American until visiting Massachusetts and standing upon Plymouth Rock, after World War I.