Elizabeth Blackwell (February 3, 1821 – May 31, 1910) was an abolitionist, women's rights activist, and the first female doctor in the United States.

Blackwell was born in Bristol, England, the third of nine children born to a sugar refiner, named Samuel Blackwell, who could afford to give his numerous sons, and also daughters, an education. Samuel Blackwell believed that his daughters should get the same education as boys so he had his daughters tutored. In 1832, the family emigrated to the United States, and set up a refinery in New York City. Elizabeth's family then moved to Cincinnati, three months after they moved there her father got very sick and died. After the death of her father, she took up a career in teaching in Kentucky, to make money to pay for medical school. Desiring to apply herself to the practice of medicine, she took up residence in a physician's household, using her time there to study from the family's medical library. She became active in the anti-slavery movement (as did her brother Henry Brown Blackwell). Another brother, Samuel C. Blackwell, married another important figure in women's rights, Antoinette Brown.

She attended Geneva College in New York. She was accepted there — anecdotally, because the faculty put it to a student vote, and the students thought her application a hoax — and braved the prejudice of some of the professors and students to complete her training. Blackwell overcame taunts and prejudice from the faculty as well as from her fellow students while at medical school. One anecdote relates that her anatomy instructor requested that she absent herself on a particular day, as the students would be dissecting a penis. Blackwell is said to have replied that if the instructor was upset by the fact that Student No. 156 wore a bonnet, she would be pleased to remove her conspicuous headgear and take a seat at the rear of the classroom, but that she would not voluntarily absent herself from a lecture. On January 11, 1849, she became the first woman to earn a medical degree in the United States, graduating at the top of her class.

Barred from practice in most hospitals she decided to go to Paris, France and train at La Maternatè, but while she was there her training was cut short when she caught a terrible eye infection from a baby she was working on. Later the eye got so bad she had to get it removed and replaced with a glass eye. She founded her own infirmary, the New York Infirmary for Indigent Women and Children, in 1857. When the American Civil War began, she trained nurses, and in 1868 she founded a Women's Medical College at the Infirmary to formally train women, physicians, and doctors. After American hospitals refused to hire her, she opened a clinic in New York City where she was joined by her sister Dr. Emily Blackwell and Dr. Marie E. Zakrzews.

In 1869 she left her sister Emily in charge of the College and returned to England. There, with Florence Nightingale, she opened the Women's Medical College. Blackwell taught at the newly created London School of Medicine for Women and became the first female physician and doctor in the UK Medical Register. She retired at the age of 86.

Her female education guide, The Moral Education of the Young, was published in Spain as was her autobiography, Pioneer Work in Opening the Medical Profession to Women (1895). Upon her death on May 31, 1910, she was buried in a remote part of Scotland.