From Disability Politics and Theory:

[Eugenics] continues to have a tremendous influence on views of disability today. Lennard J. Davis writes:

Eugenics saw the possible improvement of the race as being accomplished by diminishing problematic peoples and their problematic behaviors — these peoples were clearly delineated under the rubric of feeble-mindedness and degeneration as women, people of colour, homosexuals, the working class and so on. All these were considered to be categories of disability, although we do not think of them as connected in this way today. (2002: 14)

Originally, the concept of disability applied to any number of people who were considered to have genetically and socially undesirable traits. This definition of disability, upheld in the late 1800s and early 1900s, demonstrated how its categorization was used to further marginalize and control large groups of people and enforce social norms.  p. 4

In-text links used in this post:

Disability Politics and Theory

Lennard J. Davis‘ Bending Over Backwards