What key principle was established in the Supreme Court case Brown v. Board of Education?

The key principle established in the Supreme Court case Brown v. Board of Education is that racial segregation in public schools was ruled unconstitutional. This landmark decision, delivered in 1954, overturned the previous precedent set by Plessy v. Ferguson in 1896, which upheld the doctrine of "separate but equal." The Court unanimously held that segregation in public education creates a sense of inferiority among African American children that is detrimental to their educational and personal development. Therefore, the decision mandated the desegregation of public schools across America, recognizing that separate educational facilities are inherently unequal.

This case was crucial in the Civil Rights Movement, as it not only challenged segregation in schools but also set the stage for further legal challenges against racial discrimination and inequality in various settings.