Who was the first woman elected to state office in Oklahoma?

Catherine Ann "Kate" Barnard was the first woman elected to state office in Oklahoma, serving as the Commissioner of Charities and Corrections from 1915 to 1923. Her election marked a significant milestone in Oklahoma's history as she became an advocate for social reform and worked on improving conditions in state institutions.

Barnard's role not only paved the way for future women in politics but also highlighted her commitment to issues such as child welfare and prison reform during a time when women were often excluded from political processes. This historical context is essential in understanding the impact of her election and the barriers that women faced in the early 20th century.

The other individuals listed were not involved in state politics in Oklahoma. Edith T. O'Brien is less well-known in the context of Oklahoma’s political history, Florence Nightingale is recognized primarily for her contributions to nursing and healthcare, and Harriet Tubman is celebrated for her work in the abolitionist movement and the Underground Railroad. Their contributions, while significant in their own rights, do not pertain to Oklahoma's state offices.