Final answer:
The 1896 Supreme Court case that established the 'separate but equal doctrine' was Plessy v. Ferguson. This case upheld racial segregation as long as the segregated facilities were equal. It was not overturned until the 1954 Brown v. Board of Education decision, which declared state laws segregating schools unconstitutional.
Step-by-step explanation:
Landmark Supreme Court Case of 1896
The landmark Supreme Court case which established the "separate but equal doctrine" was Plessy v. Ferguson, heard in 1896. This case was pivotally centered around Homer Plessy's challenge to a Louisiana law that enforced racial segregation in public train cars. The Supreme Court, with an 8-1 majority, upheld the law, stating that provided facilities for both races were equal, then the provision of "separate but equal" accommodations did not violate the Equal Protection Clause of the Fourteenth Amendment.
Unfortunately, this decision entrenched racial discrimination legally and socially, leading to nearly six decades of Jim Crow laws until it was finally overturned by the groundbreaking Brown v. Board of Education decision in 1954. This subsequent ruling established that state laws segregating schools were unconstitutional, stating that "separate educational facilities are inherently unequal." Thus, the egregious legal doctrine that had underpinned institutionalized segregation was dismantled.