At the beginning of the 20th century, before the migration began, 90 percent of all African-Americans were living in the South. By the end of the Great Migration, nearly half of them were living outside the South in the great cities of the North and West. So when this migration began, you had a really small number of people who were living in the North and they were surviving as porters or domestics or preachers - some had risen to levels of professional jobs - but they were, in some ways, protected because they were so small.

It was illegal for black people and white people to play checkers together in Birmingham. And there were even black and white Bibles to swear to tell the truth on in many parts of the South.

And in some ways, to me, that's one of the inspiring and powerful things about the Great Migration itself. There was no leader, there was no one person who set the date who said, 'On this date, people will leave the South.' They left on their own accord for as many reasons as there are people who left. They made a choice that they were not going to live under the system into which they were born anymore and in some ways, it was the first step that the nation's servant class ever took without asking.

There are certain things that we take for granted that simply would not have existed without the great migration. Motown, for example, would not have existed - it simply would not, because Berry Gordy, the founder of it, his parents had migrated from Georgia to Detroit where he founded Motown, and where did he get his talent?

There were colored and white waiting rooms everywhere, from doctor's offices to the bus stations, as people may already know. But there were actually colored windows at the post office in, for example, Pensacola, Florida. And there were white and colored telephone booths in Oklahoma. And there were separate windows where white people and black people would go to get their license plates in Indianola, Mississippi. And there were even separate tellers to make your deposits at the First National Bank in Atlanta.

America is made up of people who came from someplace else. Even the Native Americans came over the Bering strait... America is what it is because people came from someplace else.

People leave when life becomes untenable where they are.