Sadie Tanner Mossell Alexander (January 2, 1898 – November 1, 1989) was a pioneering Black professional and civil rights activist of the early-to-mid-20th century.

There, she faced numerous hardships, due to her race and gender, such as poor advising, false accusations of plagiarism, and other students stealing her intellectual property.

Awarded the Francis Sergeant Pepper fellowship, she was able to continue her studies and in 1921 became the first African-American woman in the United States to earn a PhD from an American university.

Mossell received job offers from several Black colleges and universities, but none of them was located in Philadelphia, and she had no desire to leave her new family.

Mossell Alexander died on November 1, 1989, at Cathedral Village in Andorra, Philadelphia, from pneumonia as a complication from Alzheimer's disease.

Her maternal grandfather was Benjamin Tucker Tanner (1835–1923), a bishop in the African Methodist Episcopal Church (AME) and editor of the Christian Recorder.

[6] Her father, Aaron Albert Mossell II (1863-1951), was the first African-American graduate of the University of Pennsylvania School of Law and practiced as a lawyer in Philadelphia.

[6] During her high school years, Mossell lived in Washington, DC, with her uncle, Lewis Baxter Moore, who was dean at Howard University and her step aunt Lavinia W.

[20] On November 29, 1923, Sadie Tanner Mossell married Raymond Pace Alexander (1897–1974) in her parents' home on Diamond Street in North Philadelphia, with the ceremony performed by her father.

Alexander also can be contrasted with Howard University radicals Ralph Bunche, E. Franklin Frazier, and fellow black economist Abram Harris.

Her perspective on the New Deal is focused on advocating for reforms that ensure African American workers receive equitable benefits from government legislation.

She emphasized an urgent need for the government to enforce policies that ensure racial equity in the distribution of economic benefits and protections provided by the New Deal.

[24] During World War II, Alexander saw similarities in a rise in racial violence and discrimination in the US as paralleling the treatment of Jews in Germany.

[25] Her advocacy primarily focused on economic issues affecting Black workers and challenging structural impediments to African American rights.

In 1951, joined by Henry W. Sawyer, the Council became the Greater Philadelphia Branch of the American Civil Liberties Union; Alexander continued to serve on that organization's board of directors for many years.

[26] In 1963 she gave a speech to the Annual Conference of Commission on Human Rights and she returned to the topic of economic justice, advocating for universal employment.

[23] In a 1981 interview she did with the Geriatric Nursing journal about her position as chair of the WHCoA, Alexander expressed her disapproval of anti-abortion legislation.