The quote refers to the difficulty of American men to reintegrate into society following World War I. The majority of Americans in that era had never been more than a few hundred miles from their homes, let alone across continents. In addition, many men suffered from extreme trauma from the events they witnessed and participated in. A lot of jobs had been taken up by women, in the absence of male workers, and post-war society faced the problem of how to resolve this disparity.

The Eighteenth Amendment was the culmination of a decades long temperance movement that sought to end all alcohol sales, distribution, and consumption in America.  Initially celebrated as a progressive victory, the legal enforcement of prohibition proved a nightmare, and legions of criminal gangs began to control the illegal alcohol sales.  The Eighteenth Amendment was repealed by the Twenty First Amendment in 1933.

In Brown, Chief Justice Earl Warren expressed that in the arena of public education, "separate but equal" is inherently unequal, unfair, and unconstitutional. Plessy v. Ferguson is a prior case that upheld the "separate but equal" doctrine.

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."