Black soldiers were almost exclusively placed in segregated units, away from their white compatriots. These regiments were usually commanded by white officers. Many black soldiers were held away from the primary areas of battle, this was generally a result of the racist view of many Americans that blacks were unfit or unwilling to fight with the same efficacy as their white peers. 

The decision in Brown v. Board of Education stemmed from a case brought by an African American family from Topeka, Kansas, challenging that city’s policy of having two school systems, one for white children and one for African-Americans.  The unanimous decision in Brown outlawed racial segregation in public schools throughout the nation as a violation of the Equal Protection Clause of the Fourteenth Amendment.

 On July 26, 1948, President Harry S. Truman signed Executive Order 9981, fully integrating every branch and level of the United States Military.  Secondary Schools and State College were not integrated by court order until the 1950s, while public transportation did not get fully integrated nationwide until the 1965 Civil Rights Act.  Prisons in the south were generally segregated until the 1970s.

Prohibition was enacted following the passage of the Eighteenth Amendment. For many Americans it represented an unnecessary intrusion of rural, Protestant ideals on a key aspect of urban, working class life. The lax enforcement of the law, coupled with a significant demand for alcohol created, amongst other things, the rise of the American Mafia and widespread corruption in Politics and Civil Society. It was repealed thirteen years later, in 1933, with the passage of the Twenty-First Amendment. 

That quote is an excerpt from the Supreme Court’s ruling in the Brown v. Board of Education (1954) case. The case established that “separate but equal” was unconstitutional in practice, because it was inherently unequal. The case reversed a previous decision made by the Supreme Court, in 1896, in the Plessy v. Ferguson case, which had mandated that “separate but equal” was constitutional. It was a landmark case in the growing civil rights movement of the era.

Young women of the 1920s who dressed and behaved as such were collectively known as Flappers.

Migrants from Oklahoma and nearby states, like Arkansas, were lumped together and called "Okies."

The Roe v. Wade case made abortion legal in the United States. It dictated that a woman had the right to termination provided she was in the first trimester of her pregnancy. That has since been extended to roughly seven months, or whenever the baby could potentially live outside of the woman’s body. The case remains important in the United States today. Throughout the last few decades it has been a major social issue for several different factions and interest groups. 

Throughout the 1920s, controversies raged across the nation regarding whether Charles Darwin's theory of evolution should be taught in public schools. In 1925, the State of Tennessee passed the Butler Act, which specifically prohibited teaching evolution and allowed only creationism to be discussed in classrooms. In the tiny town of Dayton, a schoolteacher named John Scopes was convinced to challenge the law. After the American Civil Liberties Union and the famed lawyer Clarence Darrow came to Scopes' defence, William Jennings Bryan and various fundamentalist Christian groups defended the law. The subsequent trial, known popularly as the "Scopes Monkey Trial," became a celebrated national news story.

Before becoming the first African-American Supreme Court Justice, Thurgood Marshall had already made a name for himself in United States’ law and society. He argued convincingly for an end to segregation in Brown v. Board of Education, and many historians credit him with helping sway the Court in favor of ending segregation. He was appointed to the Supreme Court in 1967, having been nominated by President Lyndon B. Johnson. Marshall was a firm advocator for civil rights, constitutional amendment, and the reform of criminal procedure. He retired in 1991 and was replaced by Clarence Thomas, who became the second African-American Supreme Court Justice.